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A378432
Dirichlet inverse of A296075, where A296075 is the sum of deficiencies of divisors of n.
2
1, -2, -3, 1, -5, 8, -7, 0, 1, 12, -11, -3, -13, 16, 17, 0, -17, -4, -19, -5, 23, 24, -23, 2, 1, 28, -1, -7, -29, -44, -31, 0, 35, 36, 37, 5, -37, 40, 41, 2, -41, -60, -43, -11, -7, 48, -47, 4, 1, -8, 53, -13, -53, 0, 57, 2, 59, 60, -59, 25, -61, 64, -9, 0, 67, -92, -67, -17, 71, -92, -71, 6, -73, 76, -9, -19, 79
OFFSET
1,2
LINKS
FORMULA
a(1) = 1, and for n > 1, a(n) = -Sum_{d|n, d<n} A296075(n/d) * a(d).
PROG
(PARI)
A033879(n) = ((2*n)-sigma(n));
A296075(n) = sumdiv(n, d, A033879(d));
memoA378432 = Map();
A378432(n) = if(1==n, 1, my(v); if(mapisdefined(memoA378432, n, &v), v, v = -sumdiv(n, d, if(d<n, A296075(n/d)*A378432(d), 0)); mapput(memoA378432, n, v); (v)));
CROSSREFS
Cf. A033879.
Dirichlet inverse of A296075.
Möbius transform of A323910.
Sequence in context: A242108 A238941 A247582 * A359795 A224652 A271497
KEYWORD
sign
AUTHOR
Antti Karttunen, Nov 26 2024
STATUS
approved