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%I #12 Dec 14 2016 11:06:10
%S 2,3,4,5,6,7,8,9,10,11,12,13,14,15,18,19,20,21,22,23,24,25,26,27,28,
%T 29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,
%U 52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70
%N Indices k such that A279485(k) = 0.
%C This is different from A046039, first difference: a(14328) = 14979, A046039(14328) = 14981.
%C Conjecture: Last term is a(1040799) = 64674419. For k > 64674419 there are no more terms in this sequence (tested for k < 150000000).
%C Last terms are: 30082710, 30345655, 30358709, 30530388, 30982210, 31463972, 32369456, 32374194, 32594966, 32658048, 32780596, 32875172, 32997892, 33135812, 33440935, 33647428, 34086978, 34112787, 34629875, 35535908, 35638453, 36081828, 36140868, 36945332, 39218566, 39581363, 40364547, 40491526, 41235157, 43853600, 47973011, 57353782, 57767766, 64674419
%H Vaclav Kotesovec, <a href="/A279487/b279487.txt">Table of n, a(n) for n = 1..100000</a>
%e 3 is in the sequence because A279485(3) = 0
%e 16 is not in the sequence because A279485(16) = -1
%e 57767766 is in the sequence because A279485(57767766) = 0
%e 64674419 is in the sequence because A279485(64674419) = 0
%t nn = 10; A279485 = Rest[CoefficientList[Series[Product[(1-x^(k^4)), {k, nn}], {x, 0, nn^4}], x]]; Select[Range[nn^4], A279485[[#]]==0&]
%t nmax = 10000; nn = Floor[nmax^(1/4)]+1; poly = ConstantArray[0, nn^4 + 1]; poly[[1]] = 1; poly[[2]] = -1; poly[[3]] = 0; Do[Do[poly[[j + 1]] -= poly[[j - k^4 + 1]], {j, nn^4, k^4, -1}];, {k, 2, nn}]; A279485 = Take[poly, {2, nmax+1}]; Select[Range[nmax], A279485[[#]]==0&]
%Y Cf. A001661, A046039, A279485.
%Y Cf. A276517, A279486.
%K nonn
%O 1,1
%A _Vaclav Kotesovec_, Dec 13 2016
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