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A323365
Sum of Stern's Diatomic sequence, A002487 and its Dirichlet inverse, A317843.
10
2, 0, 0, 1, 0, 4, 0, 1, 4, 6, 0, 2, 0, 6, 12, 1, 0, 4, 0, 3, 12, 10, 0, 2, 9, 10, 8, 3, 0, -4, 0, 1, 20, 10, 18, 4, 0, 14, 20, 3, 0, 4, 0, 5, 4, 14, 0, 2, 9, 5, 20, 5, 0, 8, 30, 3, 28, 14, 0, 4, 0, 10, 20, 1, 30, -8, 0, 5, 28, 0, 0, 4, 0, 22, -2, 7, 30, 0, 0, 3, 16, 22, 0, 8, 30, 26, 28, 5, 0, 20, 30, 7, 20, 18, 42, 2, 0, 9, 4, 7, 0, 4, 0, 5, 0
OFFSET
1,1
FORMULA
a(n) = A002487(n) + A317843(n).
From Antti Karttunen, Dec 08 2021: (Start)
a(1) = 2, and for n > 1, a(n) = -Sum_{d|n, 1<d<n} A002487(d) * A317843(n/d).
a(4*n) = A002487(n).
(End)
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
A317843(n) = if(1==n, 1, -sumdiv(n, d, if(d<n, A002487(n/d)*A317843(d), 0)));
A323365(n) = (A002487(n) + A317843(n));
CROSSREFS
Cf. A002487 (also a quadrisection of this sequence), A317843.
Sequence in context: A323887 A349913 A346236 * A349135 A353336 A349126
KEYWORD
sign,look
AUTHOR
Antti Karttunen, Jan 13 2019
STATUS
approved