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 A318400 #17 Dec 03 2022 05:45:05
%S A318400 1,2,3,4,6,7,8,9,12,14,16,18,19,21,24,27,28,32,36,38,42,48,49,53,54,
%T A318400 56,57,63,64,72,76,81,84,96,98,106,108,112,114,126,128,131,133,144,
%U A318400 147,152,159,162,168,171,189,192,196,212,216,224,228,243,252,256,262
%N A318400 Numbers whose prime indices are all powers of 2 (including 1).
%C A318400 A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.
%H A318400 Amiram Eldar, <a href="/A318400/b318400.txt">Table of n, a(n) for n = 1..10000</a>
%F A318400 Sum_{n>=1} 1/a(n) = 1/Product_{k>=0} (1 - 1/prime(2^k)) = 3.81625872357742992578... . - _Amiram Eldar_, Dec 03 2022
%e A318400 The sequence of all integer partitions whose parts are all powers of 2 (including 1) begins: (), (1), (2), (11), (21), (4), (111), (22), (211), (41), (1111), (221), (8), (42), (2111), (222), (411), (11111), (2211), (81), (421), (21111), (44).
%t A318400 primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
%t A318400 pow2Q[n_]:=Or[n==1,MatchQ[FactorInteger[n],{{2,_}}]];
%t A318400 Select[Range[100],And@@pow2Q/@primeMS[#]&]
%Y A318400 Cf. A003963, A018819, A033844, A056239, A106349, A112798, A302242, A302491, A322551.
%K A318400 nonn
%O A318400 1,2
%A A318400 _Gus Wiseman_, Dec 16 2018