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A364575
a(n) = A364574(A005940(1+n)), where A364574 is the Dirichlet inverse of A005941 [the inverse permutation of A005940].
3
1, -2, -3, 0, -5, 6, 2, 0, -9, 10, 19, 0, 12, -4, 0, 0, -17, 18, 35, 0, 69, -38, -22, 0, 56, -24, -64, 0, -24, 0, 0, 0, -33, 34, 67, 0, 133, -70, -42, 0, 265, -138, -339, 0, -276, 44, 8, 0, 240, -112, -288, 0, -640, 128, 124, 0, -336, 48, 176, 0, 48, 0, 0, 0, -65, 66, 131, 0, 261, -134, -82, 0, 521, -266, -659, 0
OFFSET
0,2
LINKS
FORMULA
a(n) = A364574(A005940(1+n)).
PROG
(PARI)
A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t };
A005941(n) = { my(f=factor(n), p, p2=1, res=0); for(i=1, #f~, p = 1 << (primepi(f[i, 1])-1); res += (p * p2 * (2^(f[i, 2])-1)); p2 <<= f[i, 2]); (1+res) }; \\ (After David A. Corneth's program for A156552)
memoA364574 = Map();
A364574(n) = if(1==n, 1, my(v); if(mapisdefined(memoA364574, n, &v), v, v = -sumdiv(n, d, if(d<n, A005941(n/d)*A364574(d), 0)); mapput(memoA364574, n, v); (v)));
A364575(n) = A364574(A005940(1+n));
CROSSREFS
Cf. A005940, A005941, A085405 (reduced modulo 2), A364574.
Cf. also A324052, A324640 (scatter plots).
Sequence in context: A128214 A307865 A219695 * A267186 A248092 A145105
KEYWORD
sign,look
AUTHOR
Antti Karttunen, Aug 05 2023
STATUS
approved