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A083972
Smallest palindromic prime containing exactly n 1's.
10
313, 11, 18181, 11311, 1311131, 1114111, 110111011, 111181111, 11115151111, 1011117111101, 1110111110111, 1111118111111, 111111212111111, 111111151111111, 11121111111112111, 1011111110111111101, 1111111611161111111, 111110111171111011111, 1111111111111111111, 111111111161111111111, 11111111181118111111111, 1101111111119111111111011
OFFSET
1,1
LINKS
MATHEMATICA
digOfInterest = 1;
primes = {};
While[Length[primes] < 6,
n = Length[primes] + 1;
i = 0;
While[Length[primes] != n,
i++;
dig = IntegerDigits[Prime[i]];
If[
(dig == Reverse[dig]) &&
(Count[dig, digOfInterest] == n),
AppendTo[primes, FromDigits[dig]];
];
];
];
primes
(* Kevin Southwick, Jul 25 2015 *)
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 21 2003
EXTENSIONS
More terms from David Wasserman, Dec 06 2004
Corrected and extended by Giovanni Resta, Feb 08 2006
2 more terms from Erich Friedman, Mar 23 2008
STATUS
approved