A076651 a(n) = floor( sqrt( p * (p+2) / 2)) where p is the lesser of the twin primes.

2, 4, 8, 12, 21, 29, 42, 50, 72, 76, 97, 106, 127, 135, 140, 161, 169, 190, 199, 220, 246, 296, 305, 326, 369, 403, 424, 436, 453, 466, 572, 581, 585, 606, 623, 721, 729, 742, 750, 772, 814, 869, 903, 912, 920, 933, 1009, 1026, 1047, 1052, 1137, 1145, 1179

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Mathematica

a = Select[ Range[300], PrimeQ[ Prime[ # ] + 2] & ]; Floor[ Sqrt[ Prime[a]*Prime[a + 1]/2 ]]
Floor[Sqrt[Times@@#/2]]&/@Select[Partition[Prime[Range[500]], 2, 1], #[[2]] - #[[1]]==2&] (* Harvey P. Dale, Jun 13 2013 *)

Crossrefs

Cf. A001359.

Sequence in context: A294066 A163489 A095352 * A368986 A081410 A217694

Adjacent sequences: A076648 A076649 A076650 * A076652 A076653 A076654

Keyword

nonn

Author

Cino Hilliard and Robert G. Wilson v, Oct 20 2002

Status

approved