A126702 a(n) = prime(!n), where !n is subfactorial n.

2, 3, 23, 193, 1697, 15907, 161773, 1777543, 21084257, 269475737, 3696588877, 54223012561, 847458120167, 14065357995331, 247134401977037, 4583801628003613, 89514011909036503, 1836054207193376321

Offset

2,1

Links

Table of n, a(n) for n=2..19.

Kim Walisch, Fast C++ prime counting function implementation (primecount).

Formula

a(n) = A000040(A000166(n)). - Amiram Eldar, Aug 27 2020

Example

a(3) = 23,because !4 = 9 and the 9th prime is 23.

Mathematica

Prime[Subfactorial[Range[2, 15]]] (* Harvey P. Dale, Nov 11 2011 *)

Crossrefs

Cf. A000040, A000166, A126701.

Sequence in context: A009180 A359840 A041459 * A260126 A260125 A020458

Adjacent sequences: A126699 A126700 A126701 * A126703 A126704 A126705

Keyword

nonn,hard,more

Author

Shyam Sunder Gupta, Feb 11 2007

Extensions

a(16)-a(19) using Kim Walisch's primecount, from Amiram Eldar, Aug 27 2020

Status

approved