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A108270 Numbers n such that n*n! + (smallest prime >= n) is prime. 1
1, 4, 6, 8, 30, 40, 164, 176, 189, 218, 370, 597, 603, 1473, 2176, 2436, 2548, 2732, 4758, 5574 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Note that Maple, PARI etc. have different notions of what "next prime" means!

LINKS

Table of n, a(n) for n=1..20.

FORMULA

A096986 INTERSECT A018252. - R. J. Mathar, Aug 13 2007

MATHEMATICA

Select[Range[5600], PrimeQ[# (#!) +NextPrime[#-1]]&] (* Harvey P. Dale, Oct 07 2019 *)

PROG

(PARI) for(x=1, 1000, if(isprime(x*x!+nextprime(x)), print1(x, ", ")))

CROSSREFS

Cf. A096986.

Sequence in context: A300658 A089330 A227553 * A019161 A291718 A137026

Adjacent sequences:  A108267 A108268 A108269 * A108271 A108272 A108273

KEYWORD

nonn,more

AUTHOR

Jorge Coveiro, Jul 24 2006

EXTENSIONS

a(11)-a(20) from Donovan Johnson, Dec 13 2008

STATUS

approved

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Last modified June 13 20:25 EDT 2021. Contains 345009 sequences. (Running on oeis4.)