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 A357636 #6 Oct 10 2022 20:47:00 %S A357636 1,4,9,12,16,25,30,36,49,63,64,70,81,90,100,108,121,144,154,165,169, %T A357636 192,196,210,225,256,273,286,289,300,324,325,360,361,400,441,442,462, %U A357636 480,484,525,529,550,561,576,588,595,625,646,676,700,729,741,750,784 %N A357636 Numbers k such that the skew-alternating sum of the partition having Heinz number k is 0. %C A357636 We define the skew-alternating sum of a sequence (A, B, C, D, E, F, G, ...) to be A - B - C + D + E - F - G + .... %C A357636 The Heinz number of a partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k). This gives a bijective correspondence between positive integers and integer partitions. %e A357636 The terms together with their prime indices begin: %e A357636 1: {} %e A357636 4: {1,1} %e A357636 9: {2,2} %e A357636 12: {1,1,2} %e A357636 16: {1,1,1,1} %e A357636 25: {3,3} %e A357636 30: {1,2,3} %e A357636 36: {1,1,2,2} %e A357636 49: {4,4} %e A357636 63: {2,2,4} %e A357636 64: {1,1,1,1,1,1} %e A357636 70: {1,3,4} %e A357636 81: {2,2,2,2} %e A357636 90: {1,2,2,3} %e A357636 100: {1,1,3,3} %e A357636 108: {1,1,2,2,2} %e A357636 121: {5,5} %e A357636 144: {1,1,1,1,2,2} %t A357636 primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]]; %t A357636 skats[f_]:=Sum[f[[i]]*(-1)^(1+Ceiling[(i+1)/2]),{i,Length[f]}]; %t A357636 Select[Range[1000],skats[Reverse[primeMS[#]]]==0&] %Y A357636 The version for original alternating sum is A000290. %Y A357636 The half-alternating form is A000583, non-reverse A357631. %Y A357636 The version for standard compositions is A357628, non-reverse A357627. %Y A357636 The non-reverse version is A357632. %Y A357636 Positions of zeros in A357634, non-reverse A357630. %Y A357636 These partitions are counted by A357640, half A357639. %Y A357636 A056239 adds up prime indices, row sums of A112798. %Y A357636 A316524 gives alternating sum of prime indices, reverse A344616. %Y A357636 A351005 = alternately equal and unequal partitions, compositions A357643. %Y A357636 A351006 = alternately unequal and equal partitions, compositions A357644. %Y A357636 A357641 counts comps w/ half-alt sum 0, even A357642. %Y A357636 Cf. A003963, A035594, A053251, A055932, A357189, A357485-A357488, A357621-A357626, A357629, A357637, A357638. %K A357636 nonn %O A357636 1,2 %A A357636 _Gus Wiseman_, Oct 09 2022