A151789 a(1)=1; for n > 1, a(n)=5*4^{wt(n-1)-1}.

1, 5, 5, 20, 5, 20, 20, 80, 5, 20, 20, 80, 20, 80, 80, 320, 5, 20, 20, 80, 20, 80, 80, 320, 20, 80, 80, 320, 80, 320, 320, 1280, 5, 20, 20, 80, 20, 80, 80, 320, 20, 80, 80, 320, 80, 320, 320, 1280, 20, 80, 80, 320, 80, 320, 320, 1280, 80, 320, 320, 1280, 320, 1280, 1280, 5120

Offset: 1

Author

N. J. A. Sloane, Jun 25 2009

Keywords

• nonn
• changed

Comments

wt(n) is the Hamming weight = binary weight of n (A000120).

Crossrefs

Cf. A000120.

Programs

Mathematica

nxt[{n_,a_}]:={n+1,5*4^(Total[IntegerDigits[n,2]]-1)}; NestList[nxt,{1,1},70][[;;,2]] (* Harvey P. Dale, Aug 23 2025 *)