A030661 -id:A030661 - cp's OEIS frontend

A030641 a(1) = 6; for n > 1, a(n) = product of next 2 primes after a(n-1).

6, 77, 6557, 43112347, 1858675670994257, 3454675249946148511864052376019, 11934781082590483693525046199489720199194471433440678070422853

Offset: 1

N. J. A. Sloane

nonn

			The 2 primes after 77 are 79, 83, so next term is 79*83 = 6557.

Cf. A030661, A030642.

A030641 := proc(n)
    option remember ;
    if n = 1 then
        6;
    else
        A030661(procname(n-1)) ;
    end if;
end proc:
seq(A030641(n), n=1..6) ;  # R. J. Mathar, Aug 09 2019

A030642 Product of next 2 primes.

Original entry on oeis.org

2, 15, 323, 111547, 12449873237, 154999344563559225589, 24024796815132956872884975543558130445497

Offset: 1

N. J. A. Sloane

nonn

Cf. A000040, A030641.

A030642 := proc(n)
    option remember ;
    if n = 1 then
        2;
    else
        A030661(procname(n-1)) ;
    end if;
end proc:
seq(A030642(n),n=1..6) ;  R. J. Mathar, Aug 09 2019

NestList[NextPrime[#] NextPrime[NextPrime[#]]&,2,10] (* Harvey P. Dale, Jul 26 2017 *)

a(n) = A030661(a(n-1)). - R. J. Mathar, Aug 09 2019

cp's OEIS Frontend

A030641 a(1) = 6; for n > 1, a(n) = product of next 2 primes after a(n-1).

Views

Author

Keywords

Examples

Crossrefs

Programs

Maple