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 A214936 a(0) = 1, a(n) = a(n - 1) * (length of binary representation of n). 0

%I

%S 1,1,2,4,12,36,108,324,1296,5184,20736,82944,331776,1327104,5308416,

%T 21233664,106168320,530841600,2654208000,13271040000,66355200000,

%U 331776000000,1658880000000,8294400000000,41472000000000,207360000000000,1036800000000000,5184000000000000

%N a(0) = 1, a(n) = a(n - 1) * (length of binary representation of n).

%F a(0) = 1, for n > 0: a(n) = a(n - 1) * (Length of binary representation of n) = a(n - 1) * A070939(n).

%e a(4) = 12 because a(3) = 4 and 4 in binary is 100 (3 bits), and thus 4 * 3 = 12.

%t nxt[{n_,a_}]:={n+1,a*IntegerLength[n+1,2]}; Transpose[NestList[nxt,{0,1},30]][[2]] (* _Harvey P. Dale_, Oct 11 2015 *)

%o (Python)

%o t = 1

%o for n in range(1,33):

%o print t,

%o t *= len(bin(n))-2

%Y Cf. A070939.

%Y Cf. A083652: a(0)=1, for n>0: a(n)=a(n-1)+A070939(n).

%K nonn,base,easy

%O 0,3

%A _Alex Ratushnyak_, Jul 29 2012

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Last modified September 23 04:54 EDT 2020. Contains 337295 sequences. (Running on oeis4.)