A065542 a(n) is smallest prime > 7*a(n-1), a(1) = 7.

7, 53, 373, 2617, 18329, 128311, 898181, 6287273, 44010929, 308076523, 2156535743, 15095750209, 105670251529, 739691760707, 5177842324987, 36244896274921, 253714273924549, 1775999917471859, 12431999422303051

Offset

1,1

Links

Table of n, a(n) for n=1..19.

Mathematica

NextPrim[n_Integer] := Block[ {k = n + 1}, While[ !PrimeQ[k], k++ ]; Return[k]]; a[1] = 7; a[n_] := NextPrim[ 7*a[n - 1]]; Table[ a[n], {n, 1, 20} ]
NestList[NextPrime[7#]&, 7, 20] (* Harvey P. Dale, Apr 23 2019 *)

Crossrefs

Sequence in context: A056590 A223778 A223712 * A279269 A015561 A133588

Adjacent sequences: A065539 A065540 A065541 * A065543 A065544 A065545

Keyword

nonn

Author

Robert G. Wilson v, Nov 28 2001

Status

approved