|
%I #25 Mar 05 2023 12:09:56
%S 5,7,17,23,31,41,47,71,79,97,113,127,151,167,191,223,233,239,241,263,
%T 271,281,337,353,367,383,431,439,449,457,463,479,521,569,577,599,601,
%U 607,617,631,641,647,673,743,751,761,769,809,839,863,881,887,911,929,953
%N Primes prime(k) such that ( 8*(prime(k-1) - prime(k-2)) ) | (prime(k)^2 - 1).
%e 5 is a term since (5^2 - 1) / (8*(3-2)) = 24/8 = 3.
%e 97 is a term since (97^2 - 1) / 8*(89-83)= 9408/48 = 196.
%t Select[Partition[Prime[Range[200]], 3, 1], Divisible[(#[[3]]^2 - 1)/8, #[[2]] - #[[1]]] &][[;; , 3]] (* _Amiram Eldar_, Feb 11 2023 *)
%Y Cf. A000040, A001248.
%K nonn
%O 1,1
%A _Najeem Ziauddin_, Feb 11 2023
|
