cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A108270 Numbers k such that k*k! + (smallest prime >= k) is prime.

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%I A108270 #15 Aug 31 2025 01:21:18
%S A108270 1,4,6,8,30,40,164,176,189,218,370,597,603,1473,2176,2436,2548,2732,
%T A108270 4758,5574
%N A108270 Numbers k such that k*k! + (smallest prime >= k) is prime.
%C A108270 Note that Maple, PARI etc. have different notions of what "next prime" means!
%F A108270 A096986 INTERSECT A018252. - _R. J. Mathar_, Aug 13 2007
%t A108270 Select[Range[5600],PrimeQ[# (#!) +NextPrime[#-1]]&] (* _Harvey P. Dale_, Oct 07 2019 *)
%o A108270 (PARI) for(x=1,1000,if(isprime(x*x!+nextprime(x)),print1(x,",")))
%Y A108270 Cf. A096986.
%K A108270 nonn,more,changed
%O A108270 1,2
%A A108270 _Jorge Coveiro_, Jul 24 2006
%E A108270 a(11)-a(20) from _Donovan Johnson_, Dec 13 2008