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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.

A278784 Numbers m such that A000041(m) is of the form 2^7 * k for odd k.

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%I A278784 #15 May 25 2024 09:09:42
%S A278784 109,230,557,675,1094,1679,2070,2314,2594,2781,2873,3133,3498,3548,
%T A278784 3595,3601,3629,3911,4059,4171,4264,4274,4501,4568,4878,4889,5112,
%U A278784 5136,5507,5675,5907,6059,6152,6260,6490,6667,6669,6938,6961,7667,8013,8640,8729,9171
%N A278784 Numbers m such that A000041(m) is of the form 2^7 * k for odd k.
%C A278784 Numbers m such that A278478(m) = 7.
%C A278784 Also numbers m such that A000041(m) has seven times as many even divisors as odd divisors.
%H A278784 Colin Barker, <a href="/A278784/b278784.txt">Table of n, a(n) for n = 1..100</a>
%F A278784 A000041(a(n)) = A278201(n).
%t A278784 Select[Range[5000], IntegerExponent[PartitionsP[#], 2] == 7 &] (* _Amiram Eldar_, May 25 2024 *)
%o A278784 (PARI) isok(n) = valuation(numbpart(n), 2)==7;
%o A278784 select(n->isok(n), vector(9000, n, n))
%Y A278784 Cf. A000041, A278201, A278779, A278780, A278781, A278782, A278783.
%Y A278784 Positions of 7's in A278478.
%K A278784 nonn
%O A278784 1,1
%A A278784 _Colin Barker_, Nov 28 2016