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A032735
Palindromes that cannot be prefixed and followed by any digit to form a prime.
1
11111, 60806, 65356, 1115111, 1392931, 1643461, 1762671, 1797971, 1799971, 1863681, 1911191, 2005002, 2190912, 2429242, 2499942, 2512152, 2708072, 2714172, 2794972, 2845482, 2848482, 2942492, 2993992, 3150513, 3239323
OFFSET
1,1
EXAMPLE
11111 prefixed and followed with a digit from (1,2,3,4,5,6,7,8,9) never yields a prime: '2'11111'3' = 29 x 72797.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, May 15 1998
STATUS
approved