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A145742 Composite numbers n such that all 10 numbers n+4*m^2 for m=1,2,...,10 are prime. 2

%I

%S 143473,2821813,3171877,27439003,95771533,107832187,174499873,

%T 315915517,438561313,761271373,1010315923,1083101167,1247119687,

%U 1272171217,1494582637,1540272427,2760699643,3205014607,3615583147,3636010807

%N Composite numbers n such that all 10 numbers n+4*m^2 for m=1,2,...,10 are prime.

%C There is no further term up to 2*10^8.

%e 174499873 is composite and all 10 numbers 174499873+4m^2 for m=1,2,...,10 are prime.

%t Select[Range[140001,364*10^7,2],CompositeQ[#]&&AllTrue[#+{4,16,36,64,100,144,196,256,324,400},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Jun 12 2017 *)

%Y Cf. A145741, A145743.

%K nonn

%O 1,1

%A _Farideh Firoozbakht_, Oct 17 2008

%E a(8)-a(20) from _Donovan Johnson_, Nov 17 2008

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Last modified October 26 02:14 EDT 2021. Contains 348256 sequences. (Running on oeis4.)