

A066876


Numbers n such that prime(n+2) + prime(n2) = 2*prime(n).


1



5, 6, 7, 27, 28, 36, 41, 54, 80, 82, 94, 126, 127, 131, 160, 177, 236, 248, 287, 339, 362, 385, 387, 400, 401, 410, 432, 433, 477, 485, 566, 579, 580, 581, 586, 599, 689, 700, 735, 744, 793, 821, 863, 874, 954, 1031, 1043, 1069, 1081, 1113, 1143, 1145, 1193
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OFFSET

1,1


COMMENTS

If (prime(n+2) + prime(n2))/prime(n) is integer, that can only be 2.


LINKS



MATHEMATICA

Select[Range[3, 1200], Prime[ # ] == (Prime[ # + 2] + Prime[ #  2])/2 &] (* Ray Chandler, Jan 09 2007 *)
Flatten[Position[Partition[Prime[Range[1200]], 5, 1], _?(#[[1]]+#[[5]] == 2#[[3]]&), 1, Heads>False]]+2 (* Harvey P. Dale, Jan 01 2022 *)


PROG

(PARI) { n=0; for (m=3, 10^10, if (prime(m+2) + prime(m2) == 2*prime(m), write("b066876.txt", n++, " ", m); if (n==1000, return)) ) } \\ Harry J. Smith, Apr 03 2010


CROSSREFS



KEYWORD

nonn


AUTHOR



EXTENSIONS



STATUS

approved



