OFFSET
1,1
MATHEMATICA
NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; f[n_] := ToExpression[ ToString[n] <> ToString[ NextPrim[n]]]; NestList[f, 3, 7]
NestList[FromDigits[Join[IntegerDigits[#], IntegerDigits[NextPrime[ #]]]]&, 3, 6] (* Harvey P. Dale, Apr 05 2015 *)
CROSSREFS
KEYWORD
easy,nonn,base
AUTHOR
Robert G. Wilson v, Feb 10 2002
STATUS
approved