OFFSET
1,1
MATHEMATICA
s = {7, 7, 7, 7, 7, 7, 7}; lst = {}; k = 1; While[k < 10001, l = 1; il = 12;
While[l < il, p = FromDigits@ Flatten@ Insert[ IntegerDigits[k, 10, 10], s, l];
If[PrimeQ@ p, AppendTo[lst, p]]; l++]; k++]; Union@ lst (* Robert G. Wilson v, Feb 08 2018 *)
PROG
(PARI) is(n) = my(v=vector(7, x, 7), d=digits(n)); for(k=1, #d-6, if([d[k], d[k+1], d[k+2], d[k+3], d[k+4], d[k+5], d[k+6]]==v, return(1))); 0
forprime(p=1, , if(is(p), print1(p, ", "))) \\ Felix Fröhlich, Mar 06 2018
CROSSREFS
KEYWORD
base,nonn,less
AUTHOR
Yohei Furutono, Jan 25 2018
STATUS
approved