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A126702 a(n) = prime(!n), where !n is subfactorial n. 0

%I #12 Aug 27 2020 03:36:35

%S 2,3,23,193,1697,15907,161773,1777543,21084257,269475737,3696588877,

%T 54223012561,847458120167,14065357995331,247134401977037,

%U 4583801628003613,89514011909036503,1836054207193376321

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

%H Kim Walisch, <a href="https://github.com/kimwalisch/primecount">Fast C++ prime counting function implementation (primecount)</a>.

%F a(n) = A000040(A000166(n)). - _Amiram Eldar_, Aug 27 2020

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

%t Prime[Subfactorial[Range[2,15]]] (* _Harvey P. Dale_, Nov 11 2011 *)

%Y Cf. A000040, A000166, A126701.

%K nonn,hard,more

%O 2,1

%A _Shyam Sunder Gupta_, Feb 11 2007

%E a(16)-a(19) using Kim Walisch's primecount, from _Amiram Eldar_, Aug 27 2020

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Last modified April 24 22:17 EDT 2024. Contains 371964 sequences. (Running on oeis4.)