A142340 Primes of the form (p(n)-2*n)/7, where p(n)=n-th prime.

3, 5, 7, 7, 23, 23, 43, 67, 71, 73, 127, 127, 151, 163, 173, 181, 199, 199, 229, 239, 257, 271, 293, 353, 383, 419, 419, 457, 463, 479, 487, 523, 571, 599, 601, 617, 631, 643, 643, 673, 733, 739, 739, 761, 821, 827, 827, 863, 881, 881, 887, 907, 937, 967, 1033

Offset

1,1

Links

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

Example

If n=16, then (p(16)-2*16)/7=(53-32)/7=3=a(1).
If n=22, then (p(22)-2*22)/7=(79-44)/7=5=a(2).
If n=26, then (p(26)-2*26)/7=(101-52)/7=7=a(3).
If n=27, then (p(27)-2*27)/7=(103-54)/7=7=a(4).
If n=60, then (p(60)-2*60)/7=(281-120)/7=23=a(5), etc.

Maple

for n from 1 to 3000 do p := (ithprime(n)-2*n)/7 ; if type(p, 'integer') then if isprime(p) then printf("%d, ", p) ; end if; end if; end do: # R. J. Mathar, Apr 28 2010

Mathematica

Select[Table[(Prime[n]-2n)/7, {n, 2000}], PrimeQ] (* Harvey P. Dale, Sep 19 2020 *)

Crossrefs

Cf. A000040.

Sequence in context: A202124 A201088 A201042 * A185168 A131979 A335894

Adjacent sequences: A142337 A142338 A142339 * A142341 A142342 A142343

Keyword

nonn

Author

Juri-Stepan Gerasimov, Oct 07 2008

Extensions

More terms from R. J. Mathar, Apr 28 2010

Status

approved