A079329 Let g(n)=A006512(n) be the larger member of the n-th pair of twin primes. Then a(n) is the average of g(n) and g(n+1).

6, 10, 16, 25, 37, 52, 67, 88, 106, 124, 145, 166, 187, 196, 214, 235, 256, 277, 298, 331, 385, 427, 448, 493, 547, 586, 610, 631, 652, 736, 817, 826, 844, 871, 952, 1027, 1042, 1057, 1078, 1123, 1192, 1255, 1285, 1297, 1312, 1375, 1441, 1468, 1486, 1549

Offset

1,1

Links

Table of n, a(n) for n=1..50.

Eric Weisstein's World of Mathematics, Twin Primes

Formula

a(n)=Sum_{x=n-th greater of twin primes..(n+1)th greater of twin primes}-(-1)^x*x - Juri-Stepan Gerasimov, Jul 14 2009

Mathematica

s=Select[Range[2000], PrimeQ[ # ]&&PrimeQ[ #-2]&]; (Drop[s, 1]+Drop[s, -1])/2

Crossrefs

Cf. A006512, A079328.

Sequence in context: A340773 A114975 A230276 * A302748 A020741 A274287

Adjacent sequences: A079326 A079327 A079328 * A079330 A079331 A079332

Keyword

nonn

Author

Vincenzo Origlio (vincenzo.origlio(AT)itc.cnr.it), Feb 13 2003

Extensions

Edited by Dean Hickerson, Feb 14 2003

Status

approved