OFFSET
1,8
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
Ralf Stephan, Some divide-and-conquer sequences with (relatively) simple ordinary generating functions, 2004.
Ralf Stephan, Table of generating functions.
FORMULA
MATHEMATICA
a[n_] := DigitCount[n, 2, 0] + IntegerDigits[n, 2][[2]] - 1; a[1] = 0; Array[a, 100] (* Amiram Eldar, Jul 16 2023 *)
PROG
(PARI) for(n=1, 120, l=ceil(log(n)/log(2)); t=polcoeff(1/(1-x)*sum(k=0, l, (x^2^(k+2))/(1+x^2^k)) + O(x^(n+1)), n); print1(t", "))
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Ralf Stephan, Jun 14 2003
STATUS
approved