A388282 a(n) = A276086(n) * A276086(sigma(n)-n), where A276086 is the primorial base exp-function, and sigma is the sum of divisors function.

2, 6, 12, 54, 36, 25, 20, 150, 270, 675, 180, 5625, 100, 3375, 4500, 33750, 900, 93750, 500, 421875, 67500, 84375, 4500, 21875, 6250, 421875, 187500, 31640625, 22500, 1225, 28, 294, 6300, 23625, 6300, 306250, 140, 118125, 94500, 826875, 1260, 765625, 700, 165375, 44100, 2953125, 6300, 9646875, 26250, 918750, 3937500

Offset

1,1

Links

Antti Karttunen, Table of n, a(n) for n = 1..11550

Index entries for sequences related to primorial base.

Index entries for sequences related to sigma(n).

Formula

a(n) = A276086(n) * A379493(n).

a(n) >= A388031(n), with equivalence iff n is one of the terms A388280.

Prog

(PARI)
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A388282(n) = (A276086(n)*A276086(sigma(n)-n));

Crossrefs

Cf. A000203, A001065, A276086, A379493, A388031, A388280, A388281.

Sequence in context: A369330 A152873 A175810 * A083001 A285079 A119862

Adjacent sequences: A388279 A388280 A388281 * A388283 A388284 A388285

Keyword

nonn

Author

Antti Karttunen, Sep 16 2025

Status

approved