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 A085955 #13 Dec 14 2019 08:09:26 %S A085955 4,6,9,16,20,22,24,28,36,38,49,56,65,69,70,72,84,86,92,100,104,105, %T A085955 118,130,132,133,134,138,148,150,152,153,162,166,176,180,184,208,209, %U A085955 212,214,216,256,258,259,261,262,264,266,267,278,284,320,325,326,329,345 %N A085955 Composites such that the number of 1's in their binary expansion is equal to the number of 1's in the binary expansion of the sum of their prime factors (counting repetition). %H A085955 Amiram Eldar, <a href="/A085955/b085955.txt">Table of n, a(n) for n = 1..10000</a> %e A085955 a(42) = 216 because 216 = '11011000' and sopfr(216) = 15 = '1111'; both have four 1's. %t A085955 binWt[n_] := DigitCount[n, 2, 1]; seqQ[n_] := CompositeQ[n] && binWt[n] == binWt[Plus @@ Times @@@ FactorInteger[n]]; Select[Range[350], seqQ] (* _Amiram Eldar_, Dec 14 2019 *) %Y A085955 Cf. A000120, A001414, A002808, A064548. %K A085955 easy,nonn,base %O A085955 1,1 %A A085955 _Jason Earls_, Aug 17 2003