login
Centered 11-gonal (or hendecagonal) primes.
1

%I #80 May 27 2022 15:33:41

%S 67,397,727,859,1321,2311,3037,3301,4159,8581,10891,12409,19471,28909,

%T 47059,51217,63559,64747,78541,79861,95107,100981,108571,119659,

%U 134707,139921,156157,177211,195427,203809,221101,257797,264991,284659,287167,294757,307627,315481

%N Centered 11-gonal (or hendecagonal) primes.

%C Primes of the form (11*k^2 - 11*k + 2)/2.

%H OEIS Wiki, <a href="https://oeis.org/wiki/Figurate_numbers">Figurate numbers</a>

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

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

%p select(isprime, [(11*k^2-11*k+2)/2$k=1..300])[]; # _Alois P. Heinz_, May 27 2022

%o (PARI) for(n=1, 1e3, if(isprime(k=(11*n^2-11*n+2)/2), print1(k,", "))) \\ _Altug Alkan_, Nov 26 2015

%Y Intersection of A069125 and A000040.

%K nonn

%O 1,1

%A _Ilya Gutkovskiy_, Nov 26 2015

%E a(15)=47059 inserted by _Georg Fischer_, May 27 2022