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A088271
Palindromic primes that yield a prime when sandwiched between two 7's. (Prefixing and suffixing a 'seven' on both sides yields another pal prime).
3
2, 5, 131, 191, 797, 11411, 15551, 30203, 31013, 32423, 36263, 36563, 38183, 39293, 72227, 74747, 77477, 94349, 94949, 1003001, 1055501, 1074701, 1085801, 1120211, 1123211, 1153511, 1178711, 1183811, 1221221, 1311131, 1317131, 1363631
OFFSET
1,1
EXAMPLE
191 is a member as 71917 is also a prime.
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Sep 28 2003
EXTENSIONS
More terms from David Wasserman, Jul 28 2005
STATUS
approved