OFFSET
1,4
COMMENTS
See A216982 for definition of anti-Chowla's function.
MAPLE
PROG
(PARI) a(n)=if(n<4, 0, my(k=valuation(n, 2)); sigma(n)+sigma(2*n+1)+sigma(2*n-1)+sigma(n>>k)<<(k+1)-3-23*n\/3) \\ Charles R Greathouse IV, Mar 05 2013
CROSSREFS
KEYWORD
nonn,less
AUTHOR
Juri-Stepan Gerasimov, Mar 04 2013
EXTENSIONS
a(16) corrected by Charles R Greathouse IV, Mar 05 2013
STATUS
approved