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Primes of the form (p(2n)-p(n))/(7*2, ), where p(n)=n-th prime.

Select[Table[(Prime[2n]-Prime[n])/14, {n, 3000}], PrimeQ] (* Harvey P. Dale, Feb 01 2019 *)

Definition clarified by Harvey P. Dale, Feb 01 2019

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_Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), _, Sep 18 2008

Cf. A072473. [From _R. J. Mathar (mathar(AT)strw.leidenuniv.nl), _, Oct 04 2008]

More terms from _R. J. Mathar (mathar(AT)strw.leidenuniv.nl), _, Oct 04 2008

Primes of the form (p(2n)-p(n))/7*2, where p(n)=n-th prime.

3, 19, 41, 173, 181, 281, 347, 373, 401, 409, 433, 449, 461, 461, 479, 499, 509, 541, 547, 571, 577, 619, 691, 701, 709, 859, 881, 919, 929, 1087, 1091, 1093, 1097, 1193, 1229, 1367, 1367, 1481, 1483, 1511, 1523, 1553, 1559, 1579, 1601, 1667, 1697, 1699

1,1

If n=10, then (p(10*2)-p(10))/7*2=(71-29)/14=3=a(1).

If n=45, then (p(45*2)-p(45))/7*2=(463-197)/14=19=a(2).

If n=85, then (p(85*2)-p(85))/7*2=(1013-439)/14=41=a(3).

If n=300, then (p(300*2)-p(300))/7*2=(4409-1987)/14=173=a(4).

If n=311, then (p(311*2)-p(311))/7*2=(4597-2063)/14=181=a(5).

If n=459, then (p(459*2)-p(459))/7*2=(7187-3253)/14=281=a(6), etc.

Cf. A000040.

Cf. A072473. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 04 2008]

nonn

Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), Sep 18 2008

More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 04 2008

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