A186944 Geometric mean of n-th row of A080508.

1, 2, 2, 6, 6, 30, 30, 210, 210, 210, 210, 2310, 2310, 30030, 30030, 30030, 30030, 510510, 510510, 9699690, 9699690, 9699690, 9699690, 223092870, 223092870, 223092870, 223092870, 223092870, 223092870, 6469693230, 6469693230, 200560490130, 200560490130

Offset

1,2

Links

Table of n, a(n) for n=1..33.

Formula

For n != 2, a(n) = A034386(n-1). - Jeppe Stig Nielsen, Nov 04 2018

Prog

(PARI) a(n) = {if (n == 1, return (1)); if (n == 2, return (2)); f  = factor((n-1)!); prod(i=1, #f~, f[i, 1]); } \\ Michel Marcus, Aug 30 2013
(PARI) a(n) = if(n==2, 2, prod(i=1, primepi(n-1), prime(i))) \\ Jeppe Stig Nielsen, Nov 04 2018

Crossrefs

Cf. A080509.

Sequence in context: A056038 A076929 A265642 * A247525 A305295 A174789

Adjacent sequences: A186941 A186942 A186943 * A186945 A186946 A186947

Keyword

nonn

Author

Michel Marcus, Aug 30 2013

Status

approved