OFFSET
1,1
COMMENTS
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
a(1)=3 because prime(1)=2 and 7*2+1=17 (prime).
MATHEMATICA
dnp[n_]:=Module[{c=7*Prime[n]}, NextPrime[c]-c]; Array[dnp, 100] (* Harvey P. Dale, Jan 14 2022 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Zak Seidov, Nov 18 2005
STATUS
approved