A260656 a(n) = lcm{!2, !3, ..., !n}, where !n = A000166(n) is subfactorial.

1, 2, 18, 396, 104940, 10808820, 160327227060, 486432806900040, 72152091814676033160, 105952244289903723626034120, 1697305261921685687642685992397720, 108004858262683508632706244802225075247640, 266448824855803491635798907952730108331437779905720

Offset: 2

Author

Vladimir Reshetnikov, Nov 13 2015

Keywords

• nonn

Comments

a(n) <= A131631(n).

Examples

			For n = 5, a(5) = lcm(!2, !3, !4, !5) = lcm(1, 2, 9, 44) = 396.
		

Links

• Alois P. Heinz, Table of n, a(n) for n = 2..45
• Index entries for sequences related to lcm's

Crossrefs

Cf. A000166, A131631.

Programs

Maple

b:= proc(n) option remember;
     `if`(n=0, 1, n*b(n-1)+(-1)^n)
    end:
a:= n-> ilcm(seq(b(i), i=2..n)):
seq(a(n), n=2..15);  # Alois P. Heinz, May 08 2020

Mathematica

LCM@@@Subfactorial@Range[2, Range[2, 14]]

PARI

a(n) = lcm(vector(n-1, k, if(k+1,round((k+1)!/exp(1)),1))); \\ Altug Alkan, Nov 13 2015