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 A278780 #19 May 25 2024 09:08:06 %S A278780 11,21,75,94,98,116,120,125,128,130,133,137,141,142,180,206,231,236, %T A278780 243,248,255,268,292,297,303,305,322,334,340,350,364,386,397,413,415, %U A278780 469,471,487,494,515,550,554,605,606,609,628,631,662,676,692,699,744,745 %N A278780 Numbers m such that A000041(m) is of the form 2^3 * k for odd k. %C A278780 Numbers m such that A278478(m) = 3. %C A278780 Also numbers m such that A000041(m) has three times as many even divisors as odd divisors. %H A278780 Colin Barker, <a href="/A278780/b278780.txt">Table of n, a(n) for n = 1..1000</a> %F A278780 A000041(a(n)) = A278197(n). %t A278780 Select[Range[750], IntegerExponent[PartitionsP[#], 2] == 3 &] (* _Amiram Eldar_, May 25 2024 *) %o A278780 (PARI) isok(n) = valuation(numbpart(n),2)==3; %o A278780 select(n->isok(n), vector(1000, n, n)) %Y A278780 Cf. A000041, A278197, A278779, A278781, A278782, A278783, A278784. %Y A278780 Positions of 3's in A278478. %K A278780 nonn %O A278780 1,1 %A A278780 _Colin Barker_, Nov 28 2016