OFFSET
1,1
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
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Nov 28 2001
STATUS
approved