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A202422 Primes of the form n!*n!! + 1. 1
2, 5, 19, 193, 1801, 56240459218944001, 112873711099106889552388221969528619131820978659655680000000000001 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

For n > 4, the last digits of the prime numbers are of the form 01, 001, 0000000000001,...,...000001.

Generated by n = 1, 2, 3, 4, 5, 14, 37, 48, 50, 52,... - R. J. Mathar, Dec 21 2011

LINKS

Table of n, a(n) for n=1..7.

EXAMPLE

19 is in the sequence because, for n = 3, 3!*3!! + 1 = 6*3 + 1 = 19.

MATHEMATICA

a={}; Do[p=n!*n!!+1; If[PrimeQ[p], AppendTo[a, p]], {n, 10^3}]; Print[a];

CROSSREFS

Cf. A000142, A006882.

Sequence in context: A108799 A193674 A085871 * A212269 A080280 A218386

Adjacent sequences:  A202419 A202420 A202421 * A202423 A202424 A202425

KEYWORD

nonn

AUTHOR

Michel Lagneau, Dec 19 2011

STATUS

approved

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Last modified March 26 10:18 EDT 2019. Contains 321491 sequences. (Running on oeis4.)