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A048403
Primes with consecutive digits that differ exactly by 6.
6
2, 3, 5, 7, 17, 71, 1717171717171717171717171717171, 1717171717171717171717171717171717171
OFFSET
1,1
COMMENTS
From Andrew Howroyd, Aug 13 2024: (Start)
Terms with more than 1 digit have digits alternating between 1 and 7.
No more terms < 10^3000. (End)
PROG
(PARI) upto(limit)={my(L=List([t|t<-[2, 3, 5], t<=limit]), m=1); while(m<limit, foreach([m*17\10, m*71\10, m*17, m*71], t, if(isprime(t)&&t<=limit, listput(L, t))); m=m*100+1); Vec(L)}
upto(10^100) \\ Andrew Howroyd, Aug 13 2024
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Apr 15 1999
EXTENSIONS
Offset changed by Andrew Howroyd, Aug 13 2024
STATUS
approved