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A317838
a(n) = Sum_{d|n} A002487(d).
5
1, 2, 3, 3, 4, 6, 4, 4, 7, 8, 6, 9, 6, 8, 10, 5, 6, 14, 8, 12, 14, 12, 8, 12, 11, 12, 15, 12, 8, 20, 6, 6, 14, 12, 16, 21, 12, 16, 18, 16, 12, 28, 14, 18, 26, 16, 10, 15, 13, 22, 20, 18, 14, 30, 20, 16, 20, 16, 12, 30, 10, 12, 24, 7, 16, 28, 12, 18, 24, 32, 14, 28, 16, 24, 35, 24, 26, 36, 14, 20, 29, 24, 20, 42, 30, 28, 28, 24
OFFSET
1,2
COMMENTS
Inverse Möbius transform of A002487, Stern's Diatomic sequence.
FORMULA
a(n) = Sum_{d|n} A002487(d).
a(n) = A317837(n) + A002487(n).
PROG
(PARI)
A002487(n) = { my(a=1, b=0); while(n>0, if(bitand(n, 1), b+=a, a+=b); n>>=1); (b); }; \\ From A002487
A317838(n) = sumdiv(n, d, A002487(d));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Aug 09 2018
STATUS
approved