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A166604 Numbers k such that Sum_{i=1..k} i^4 divides Product_{i=1..k} i^4. 7

%I

%S 1,31,59,94,104,122,133,181,206,223,244,248,283,298,318,342,356,401,

%T 406,421,422,439,444,449,451,469,479,493,496,507,528,532,536,541,555,

%U 597,631,637,643,668,701,706,712,717,721,722,754,762,795,797,801,815,842

%N Numbers k such that Sum_{i=1..k} i^4 divides Product_{i=1..k} i^4.

%H Harvey P. Dale, <a href="/A166604/b166604.txt">Table of n, a(n) for n = 1..3000</a>

%e a(2) = A125314(4) = 31.

%t k = s = 1; p = 1; lst = {}; While[k < 1000, If[ Mod[p, s] == 0, AppendTo[lst, k]]; k++; s = s + k^4; p = p*k^4]; lst (* _Robert G. Wilson v_, Nov 02 2009 *)

%t Module[{nn=1000,c},c=Range[nn]^4;Select[Range[nn],Divisible[Times@@ Take[ c,#], Total[Take[c,#]]]&]] (* _Harvey P. Dale_, Dec 18 2013 *)

%Y Cf. A125314, A166602, A060462, A166605, A166606, A166607, A166608, A166609, A166610.

%K nonn

%O 1,2

%A _Alexander Adamchuk_, Oct 18 2009

%E a(15) - a(53) from _Robert G. Wilson v_, Nov 02 2009

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Last modified April 22 14:18 EDT 2019. Contains 322349 sequences. (Running on oeis4.)