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A346093
a(n) = A276085(A328571(A108951(n))).
6
1, 2, 6, 2, 30, 6, 210, 8, 36, 30, 2310, 6, 30030, 210, 30, 8, 510510, 36, 9699690, 30, 210, 2310, 223092870, 36, 240, 30030, 216, 210, 6469693230, 240, 200560490130, 32, 2310, 510510, 2520, 36, 7420738134810, 9699690, 30030, 240, 304250263527210, 2520, 13082761331670030, 2310, 240, 223092870, 614889782588491410, 36, 32550
OFFSET
1,2
FORMULA
a(n) = A108951(n) - A346092(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)); };
A328571(n) = { my(m=1, p=2); while(n, m *= (p^!!(n%p)); n = n\p; p = nextprime(1+p)); (m); };
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jul 09 2021
STATUS
approved