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A345930
a(n) = A344756(A276086(n)).
5
1, 1, 1, 2, 7, 1, 1, 1, 1, 13, 41, 2, 9, 11, 37, 2, 47, 3, 11, 7, 43, 19, 53, 4, 13, 17, 49, 11, 59, 1, 1, 1, 1, 17, 55, 1, 1, 1, 1, 106, 317, 19, 73, 92, 289, 127, 359, 13, 87, 113, 331, 148, 401, 11, 101, 134, 373, 169, 443, 2, 11, 13, 47, 2, 61, 17, 69, 86, 277, 121, 347, 2, 83, 107, 319, 2, 389, 31, 97, 128, 19
OFFSET
1,4
FORMULA
a(n) = A344756(A276086(n)).
a(n) = A327860(n) / A346469(n) = A327860(n) / gcd(A327860(n), A329029(n)).
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A069359(n) = (n*sumdiv(n, d, isprime(d)/d)); \\ From A069359
A344756(n) = { my(u=A003415(n)); (u/gcd(u, A069359(n))); };
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
CROSSREFS
Cf. also A342002, A346474, A346475 (compare the scatter plots).
Sequence in context: A377275 A011047 A347589 * A084794 A116691 A225592
KEYWORD
nonn,base,look
AUTHOR
Antti Karttunen, Jul 19 2021
STATUS
approved