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 A214936 #14 Mar 06 2025 14:46:51
%S A214936 1,1,2,4,12,36,108,324,1296,5184,20736,82944,331776,1327104,5308416,
%T A214936 21233664,106168320,530841600,2654208000,13271040000,66355200000,
%U A214936 331776000000,1658880000000,8294400000000,41472000000000,207360000000000,1036800000000000,5184000000000000
%N A214936 a(0) = 1, a(n) = a(n - 1) * (length of binary representation of n).
%F A214936 a(0) = 1, for n > 0: a(n) = a(n - 1) * (Length of binary representation of n) = a(n - 1) * A070939(n).
%e A214936 a(4) = 12 because a(3) = 4 and 4 in binary is 100 (3 bits), and thus 4 * 3 = 12.
%t A214936 nxt[{n_,a_}]:={n+1,a*IntegerLength[n+1,2]}; Transpose[NestList[nxt,{0,1},30]][[2]] (* _Harvey P. Dale_, Oct 11 2015 *)
%o A214936 (Python)
%o A214936 t = 1
%o A214936 for n in range(1,33):
%o A214936 print(t, end=', ')
%o A214936 t *= len(bin(n))-2
%Y A214936 Cf. A070939.
%Y A214936 Cf. A083652: a(0)=1, for n>0: a(n)=a(n-1)+A070939(n).
%K A214936 nonn,base,easy
%O A214936 0,3
%A A214936 _Alex Ratushnyak_, Jul 29 2012