One day, one decomposition
A230091: Numbers of the form k + wt(k) for exactly two distinct k, where wt(k) = A000120(k) is the binary weight of k

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2D graph, first 500 terms https://decompwlj.com/2Dgraph500terms/A230091.html

One day, one decomposition
A230044: Nonnegative numbers k such that k plus a perfect square is a triangular number

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2D graph, first 500 terms https://decompwlj.com/2Dgraph500terms/A230044.html

One day, one decomposition
A228183: Semiprimes generated by the Euler polynomial x^2 + x + 41

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2D graph, first 500 terms https://decompwlj.com/2Dgraph500terms/A228183.html

One day, one decomposition
A227916: Primes that remain prime when the leftmost digit is removed

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2D graph, first 500 terms https://decompwlj.com/2Dgraph500terms/A227916.html

One day, one decomposition
A217139: Numbers n such that phi(n) = phi(n+12), with Euler's totient function phi = A000010

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2D graph, first 500 terms https://decompwlj.com/2Dgraph500terms/A217139.html

One day, one decomposition
A216838: Odd primes for which 2 is not a primitive root

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One day, one decomposition
A215940: Difference between the n-th and the first (identity) permutation of (0,...,m-1), interpreted as a decimal number, divided by 9 (for any m for which 10! >= m! >= n)

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2D graph, first 500 terms https://decompwlj.com/2Dgraph500terms/A215940.html

One day, one decomposition
A214423: Numbers n palindromic in only one base b, 2 <= b <= 10

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2D graph, first 500 terms https://decompwlj.com/2Dgraph500terms/A214423.html

One of my favorite sequences as of the time of writing: [[A103876]] - #OEIS https://oeis.org/A103876

One of my favorite sequences as of the time of writing:

[[A103876]] - #OEIS
https://oeis.org/A103876

One day, one decomposition
A213382: Numbers n such that n^n mod (n + 2) = n

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2D graph, first 500 terms https://decompwlj.com/2Dgraph500terms/A213382.html

One day, one decomposition
A212168: Numbers n such that the maximal exponent in its prime factorization is less than the number of positive exponents (A051903(n) < A001221(n))

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2D graph, first 500 terms https://decompwlj.com/2Dgraph500terms/A212168.html

One day, one decomposition
A212166: Numbers k such that the maximum exponent in its prime factorization equals the number of positive exponents (A051903(k) = A001221(k))

3D graph, threejs - webGL https://decompwlj.com/3Dgraph/A212166.html
2D graph, first 500 terms https://decompwlj.com/2Dgraph500terms/A212166.html

Breaking News: Math Wizard Terence Tao discovers the ancient art of... factorizing factorials! Apparently, he's really excited about his groundbreaking ability to split numbers into *gasp* large chunks! Let the riveting adventure of - wait for it - #OEIS #A034258 unfold!
https://terrytao.wordpress.com/2025/03/26/decomposing-a-factorial-into-large-factors/ #MathWizard #TerenceTao #FactorizingFactorials #BreakingNews #HackerNews #ngated

One day, one decomposition
A212165: Numbers k such that the maximum exponent in its prime factorization is not less than the number of positive exponents (A051903(k) >= A001221(k))

3D graph, threejs - webGL https://decompwlj.com/3Dgraph/A212165.html
2D graph, first 500 terms https://decompwlj.com/2Dgraph500terms/A212165.html

One day, one decomposition
A212164: Numbers k such that the maximum exponent in its prime factorization is greater than the number of positive exponents (A051903(k) > A001221(k))

3D graph, threejs - webGL https://decompwlj.com/3Dgraph/A212164.html
2D graph, first 500 terms https://decompwlj.com/2Dgraph500terms/A212164.html

One day, one decomposition
A211223: Numbers k for which sigma(k) = sigma(x) + sigma(y), where k = x + y

3D graph, threejs - webGL https://decompwlj.com/3Dgraph/A211223.html
2D graph, first 500 terms https://decompwlj.com/2Dgraph500terms/A211223.html

Woot! Another sequence at the OEIS. https://oeis.org/A381708

One day, one decomposition
A210479: Primes p with p-1 and p+1 both practical: "Sandwich of the first kind"

3D graph, threejs - webGL https://decompwlj.com/3Dgraph/A210479.html
2D graph, first 500 terms https://decompwlj.com/2Dgraph500terms/A210479.html

One day, one decomposition
A209203: Values of the difference d for 4 primes in geometric-arithmetic progression with the minimal sequence {5*5^j + j*d}, j = 0 to 3

3D graph, threejs - webGL https://decompwlj.com/3Dgraph/A209203.html
2D graph, first 500 terms https://decompwlj.com/2Dgraph500terms/A209203.html