A286629 a(n) = (A000040(n)-1) * A002110(n).

2, 12, 120, 1260, 23100, 360360, 8168160, 174594420, 4908043140, 181151410440, 6016814703900, 267146572853160, 12170010541088400, 549475975930141260, 28284929999070604860, 1694636240813882325960, 111520100308944333066060, 7037302881564418258996200, 518649222371297625688019940, 39055858108868927267719077300

Offset: 1

Author

Antti Karttunen, Jul 07 2017

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..120
• Index entries for sequences related to primorial base

Crossrefs

Cf. A000040, A002110, A006093, A061720, A276154, A286630.

Programs

Mathematica

Table[(Prime[n] - 1) Product[Prime[k], {k, n}], {n, 100}] (* Indranil Ghosh, Jul 07 2017 *)

PARI

a(n) = (prime(n)-1)*prod(k=1, n, prime(k)); \\ Michel Marcus, Jul 07 2017

Python

from sympy import prime, primorial
def a002110(n): return 1 if n<1 else primorial(n)
def a(n): return (prime(n) - 1)*a002110(n)
print([a(n) for n in range(1, 21)]) # Indranil Ghosh, Jul 07 2017

Scheme

(define (A286629 n) (* (- (A000040 n) 1) (A002110 n)))

Formula

a(n) = A006093(n) * A002110(n) = (A000040(n)-1) * A002110(n).

a(n) = A286630(n) - A002110(n).

a(n) = A276154(A061720(n-1)).