A320008 a(0) = 1; for n > 0, a(n) = A000120(n) * a(n-A000120(n)), where A000120(n) is the binary weight of n.

1, 1, 1, 2, 2, 4, 4, 6, 6, 12, 12, 18, 24, 36, 54, 72, 72, 144, 144, 216, 288, 432, 648, 864, 1296, 1944, 2592, 3456, 5832, 7776, 10368, 12960, 12960, 25920, 25920, 38880, 51840, 77760, 116640, 155520, 233280, 349920, 466560, 622080, 1049760, 1399680, 1866240, 2332800, 3732480, 5598720, 6998400, 9331200, 16796160, 22394880, 27993600, 34992000

Offset: 0

Author

Antti Karttunen, Nov 24 2018

Keywords

• nonn

Comments

Sequence is monotonic because A011371 is.

Links

• Antti Karttunen, Table of n, a(n) for n = 0..133
• Index entries for sequences related to binary expansion of n

Crossrefs

Cf. A000120, A011371, A179016.

Cf. also A320002, A320009.

Programs

Mathematica

Nest[Append[#1, #2 #1[[-#2]] ] & @@ {#, Total@ IntegerDigits[Length@ #, 2]} &, {1}, 55] (* Michael De Vlieger, Nov 25 2018 *)

PARI

A320008(n) = if(0==n,1,hammingweight(n)*A320008(n-hammingweight(n)));

Formula

a(0) = 1; for n > 0, a(n) = A000120(n) * a(n-A000120(n)).