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Centered 23-gonal primes.
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%I #10 Jun 17 2021 18:39:55

%S 139,829,4831,15319,36709,53959,58789,65551,74521,107089,142969,

%T 198859,227011,278071,292561,727399,750721,804541,879199,957169,

%U 1181281,1325491,1364821,1519519,1700161,1835401,1881631,2111539,2231461,2396509,2778079,2926981,3067879

%N Centered 23-gonal primes.

%C Primes of the form (23*k^2 + 23*k + 2)/2.

%C Numbers k such that (23*k^2 + 23*k + 2)/2 is prime: 3, 8, 20, 36, 56, 68, 71, 75, 80, 96, 111, 131, 140, 155, 159, 251, 255, 264, 276, ...

%H OEIS Wiki, <a href="http://oeis.org/wiki/Centered_polygonal_numbers#cite_note-1">Centered polygonal numbers</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/CenteredPolygonalNumber.html">Centered Polygonal Number</a>

%H <a href="/index/Ce#CENTRALCUBE">Index entries for sequences related to centered polygonal numbers</a>

%t Intersection[Table[(23 k^2 + 23 k + 2)/2, {k, 0, 1000}], Prime[Range[230000]]]

%t Select[Table[(23k^2+23k+2)/2,{k,600}],PrimeQ] (* _Harvey P. Dale_, Jun 17 2021 *)

%o (PARI) lista(nn) = for(n=1, nn, if(isprime(p=(23*n^2 + 23*n + 2)/2), print1(p, ", "))); \\ _Altug Alkan_, Aug 26 2016

%Y Cf. A000040, A069174.

%Y Cf. centered k-gonal primes listed in A276261.

%K nonn

%O 1,1

%A _Ilya Gutkovskiy_, Aug 26 2016