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Search: a364574 -id:a364574
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a(n) = A364574(A005940(1+n)), where A364574 is the Dirichlet inverse of A005941 [the inverse permutation of A005940].
+20
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).
KEYWORD
sign,look
AUTHOR
Antti Karttunen, Aug 05 2023
STATUS
approved
Dirichlet inverse of A364557, which is Möbius transform of A005941.
+10
2
1, -1, -2, -1, -4, 2, -8, -1, 0, 4, -16, 2, -32, 8, 12, -1, -64, 0, -128, 4, 24, 16, -256, 2, 8, 32, 0, 8, -512, -12, -1024, -1, 48, 64, 56, 0, -2048, 128, 96, 4, -4096, -24, -8192, 16, -8, 256, -16384, 2, 48, -8, 192, 32, -32768, 0, 112, 8, 384, 512, -65536, -12, -131072, 1024, -16, -1, 224, -48, -262144, 64, 768
OFFSET
1,3
FORMULA
a(1) = 1, and for n > 1, a(n) = -Sum_{d|n, d<n} A364557(n/d) * a(d).
a(p) = -A000079(A000720(p)-1) for all primes p.
PROG
(PARI)
A364557(n) = if(1==n, 1, 2^(primepi(vecmax(factor(n)[, 1]))+(bigomega(n)-omega(n))-1));
memoA364952 = Map();
A364952(n) = if(1==n, 1, my(v); if(mapisdefined(memoA364952, n, &v), v, v = -sumdiv(n, d, if(d<n, A364557(n/d)*A364952(d), 0)); mapput(memoA364952, n, v); (v)));
CROSSREFS
KEYWORD
sign
AUTHOR
Antti Karttunen, Aug 29 2023
STATUS
approved

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