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A213675
a(n) = Chowla's function(n) + anti-Chowla's function(n).
1
0, 0, 0, 2, 2, 5, 5, 9, 5, 14, 5, 20, 10, 16, 16, 17, 17, 36, 5, 32, 18, 34, 19, 42, 27, 22, 36, 54, 5, 57, 21, 67, 40, 26, 41, 62, 25, 66, 42, 77, 14, 91, 27, 50, 88, 52, 29, 99, 46, 89, 28, 104, 53, 81, 53, 82, 58, 88, 51, 174, 16, 70, 110, 65, 59, 119, 87, 124, 34, 128
OFFSET
1,4
COMMENTS
See A216982 for definition of anti-Chowla's function.
FORMULA
a(n) = A048050(n) + A216982(n).
MAPLE
A213675 := proc(n)
A048050(n)+A216982(n) ;
end proc; # R. J. Mathar, Mar 15 2013
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
Sequence in context: A062405 A368180 A071181 * A321185 A320322 A330106
KEYWORD
nonn,less
AUTHOR
EXTENSIONS
a(16) corrected by Charles R Greathouse IV, Mar 05 2013
STATUS
approved