A286629 - OEIS

%I #19 Apr 20 2021 06:49:15

%S 2,12,120,1260,23100,360360,8168160,174594420,4908043140,181151410440,

%T 6016814703900,267146572853160,12170010541088400,549475975930141260,

%U 28284929999070604860,1694636240813882325960,111520100308944333066060,7037302881564418258996200,518649222371297625688019940,39055858108868927267719077300

%N a(n) = (A000040(n)-1) * A002110(n).

%H Antti Karttunen, <a href="/A286629/b286629.txt">Table of n, a(n) for n = 1..120</a>

%H <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>

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

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

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

%t Table[(Prime[n] - 1) Product[Prime[k], {k, n}], {n, 100}] (* _Indranil Ghosh_, Jul 07 2017 *)

%o (Scheme) (define (A286629 n) (* (- (A000040 n) 1) (A002110 n)))

%o (Python)

%o from sympy import prime, primorial

%o def a002110(n): return 1 if n<1 else primorial(n)

%o def a(n): return (prime(n) - 1)*a002110(n)

%o print([a(n) for n in range(1, 21)]) # _Indranil Ghosh_, Jul 07 2017

%o (PARI) a(n) = (prime(n)-1)*prod(k=1, n, prime(k)); \\ _Michel Marcus_, Jul 07 2017

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

%K nonn

%O 1,1

%A _Antti Karttunen_, Jul 07 2017