A373987 - OEIS

A373987

Denominator of A373158(n) / A108951(n), where A108951 is fully multiplicative and A373158 is fully additive with a(p) = p# for prime p, where x# is the primorial A034386(x).

1, 1, 1, 1, 1, 3, 1, 4, 3, 15, 1, 12, 1, 105, 5, 2, 1, 36, 1, 60, 35, 1155, 1, 4, 15, 15015, 12, 420, 1, 180, 1, 16, 1155, 255255, 105, 9, 1, 4849845, 15015, 20, 1, 1260, 1, 4620, 180, 111546435, 1, 48, 105, 900, 85085, 60060, 1, 108, 385, 70, 1616615, 3234846615, 1, 18, 1, 100280245065, 1260, 16, 5005, 13860, 1, 1021020

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OFFSET

1,6

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..4096

Index entries for sequences related to primorial numbers

FORMULA

a(n) = A108951(n) / A373985(n) = A108951(n) / gcd(A108951(n), A373158(n)).

PROG

(PARI) A373987(n) = { my(f=factor(n), m=1, s=0); for(i=1, #f~, my(x=prod(i=1, primepi(f[i, 1]), prime(i))); s += f[i, 2]*x; m *= x^f[i, 2]); m/gcd(m, s); };

(PARI) A373987(n) = denominator(A373158(n)/A108951(n));

CROSSREFS

Cf. A108951, A373158, A373985, A373986 (numerators).

Sequence in context: A316402 A054907 A245539 * A089554 A376276 A276617

Adjacent sequences: A373984 A373985 A373986 * A373988 A373989 A373990

KEYWORD

nonn,frac

AUTHOR

Antti Karttunen, Jun 25 2024

STATUS

approved