%I #22 Apr 22 2021 08:47:55

%S 1,4,18,150,1470,25410,390390,8678670,184294110,5131136010,

%T 187621103670,6217375194030,274567310987970,12474260804615610,

%U 562558737261811290,28899819781659096270,1727225399291072370690,113442860659098545705130,7154591262923825229979470,526507543922377892743899030,39613798938995626228686492690

%N a(0) = 1; for n >= 1, a(n) = A000040(n) * A002110(n).

%C The terms a(0) .. a(5), when viewed in primorial base (A049345) look as: 1, 20, 300, 5000, 70000, E00000, where "E" stands for the digit eleven.

%H Antti Karttunen, <a href="/A286630/b286630.txt">Table of n, a(n) for n = 0..120</a>

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

%F a(0) = 1; for n >= 1, a(n) = A000040(n) * A002110(n).

%F For n >= 1, a(n) = A001248(n) * A002110(n-1) = A002110(n) + A286629(n).

%t Table[If[n==0, 1, Prime[n] Product[Prime[k], {k, n}]], {n, 0, 100}] (* _Indranil Ghosh_, Jul 07 2017 *)

%o (Scheme) (define (A286630 n) (if (zero? n) 1 (* (A000040 n) (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 1 if n==0 else prime(n)*a002110(n)

%o print([a(n) for n in range(41)]) # _Indranil Ghosh_, Jul 07 2017

%o (PARI) a(n) = if (n==0, 1, prime(n)*prod(k=1, n, prime(k))); \\ _Michel Marcus_, Jul 07 2017

%Y Cf. A000040, A001248, A002110, A286629.

%Y Subsequence of A276155.

%K nonn

%O 0,2

%A _Antti Karttunen_, Jul 07 2017