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A346092
a(n) = A276085(A328572(A108951(n))).
5
0, 0, 0, 2, 0, 6, 0, 0, 0, 30, 0, 18, 0, 210, 150, 8, 0, 36, 0, 90, 1050, 2310, 0, 12, 660, 30030, 0, 630, 0, 120, 0, 0, 11550, 510510, 3780, 108, 0, 9699690, 150150, 0, 0, 0, 0, 6930, 840, 223092870, 0, 60, 11550, 1560, 2552550, 90090, 0, 216, 36960, 1470, 48498450, 6469693230, 0, 480, 0, 200560490130, 5040, 32, 360360
OFFSET
1,4
FORMULA
a(n) = A108951(n) - A346093(n).
PROG
(PARI)
A002110(n) = prod(i=1, n, prime(i));
A108951(n) = { my(f=factor(n)); prod(i=1, #f~, A002110(primepi(f[i, 1]))^f[i, 2]) };
A276085(n) = { my(f = factor(n)); sum(k=1, #f~, f[k, 2]*A002110(primepi(f[k, 1])-1)); };
A328572(n) = { my(m=1, p=2); while(n, if(n%p, m *= p^((n%p)-1)); n = n\p; p = nextprime(1+p)); (m); };
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jul 09 2021
STATUS
approved