A089691 - OEIS

A089691

a={1,3,7,9} a1={1,3,7,9,0} b[n]=Flatten[Table[10*Sum[10^m*a1[[1+Mod[m,5]]],{m,0,n}]+a,{n,0,digits}]]; a(m) = if b[n] is prime then b[n]

%I #6 Mar 30 2012 17:34:14

%S 11,13,17,19,311,313,317,31097317,731097313,109731097319,

%T 73109731097317,7310973109731097319,

%U 10973109731097310973109731097310973109731097317,31097310973109731097310973109731097310973109731097317

%N a={1,3,7,9} a1={1,3,7,9,0} b[n]=Flatten[Table[10*Sum[10^m*a1[[1+Mod[m,5]]],{m,0,n}]+a,{n,0,digits}]]; a(m) = if b[n] is prime then b[n]

%C A sum and digit set based prime generator function.

%t a={1, 3, 7, 9} a1={1, 3, 7, 9, 0} digits=100 b=Flatten[Table[10*Sum[10^m*a1[[1+Mod[m, 5]]], {m, 0, n}]+a, {n, 0, digits}]]; d=Delete[Union[c], 1]

%K nonn,base,less

%O 1,1

%A _Roger L. Bagula_, Jan 05 2004