This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A378972 #5 Dec 14 2024 20:29:53 %S A378972 0,1,-1,1,0,0,0,1,0,0,1,0,1,1,0,1,2,0,2,2,1,2,3,2,3,4,3,4,6,4,6,8,6,9, %T A378972 10,9,12,14,13,16,19,18,22,26,24,30,34,34,40,45,46,53,60,62,70,79,82, %U A378972 93,104,108,122,136,142,160,176,186,208,228,243,268 %N A378972 Second differences of the strict partition numbers A000009. %e A378972 The strict partition numbers begin (A000009): %e A378972 1, 1, 1, 2, 2, 3, 4, 5, 6, 8, 10, 12, 15, 18, 22, 27, 32, 38, ... %e A378972 with differences (A087897 without first term): %e A378972 0, 0, 1, 0, 1, 1, 1, 1, 2, 2, 2, 3, 3, 4, 5, 5, 6, 8, 8, 10, 12, ... %e A378972 with differences (a(n)): %e A378972 0, 1, -1, 1, 0, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 2, 0, 2, 2, 1, 2, ... %t A378972 Differences[Table[PartitionsQ[n],{n,0,100}],2] %Y A378972 For primes we have A036263. %Y A378972 The version for partitions is A053445. %Y A378972 For composites we have A073445. %Y A378972 For squarefree numbers we have A376590. %Y A378972 For nonsquarefree numbers we have A376593. %Y A378972 For powers of primes (inclusive) we have A376596. %Y A378972 For non powers of primes (inclusive) we have A376599. %Y A378972 Second row of A378622. See also: %Y A378972 - A293467 gives first column (up to sign). %Y A378972 - A377285 gives position of first zero in each row. %Y A378972 - A378970 gives row-sums. %Y A378972 - A378971 gives absolute value row-sums. %Y A378972 A000009 counts strict integer partitions, differences A087897, A378972. %Y A378972 A000041 counts integer partitions, differences A002865, A053445. %Y A378972 Cf. A047966, A098859, A225486, A325244, A325282. %Y A378972 Cf. A008284, A116608, A225485, A325242, A325268. %K A378972 sign %O A378972 0,17 %A A378972 _Gus Wiseman_, Dec 14 2024