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A224398 Prime numbers with m^2 digits that, if arranged in an m X m matrix, form m-digit reversible primes in each row, column, and in the two main diagonals. 2
2, 3, 5, 7, 1117, 1171, 179991179, 191797919, 337353739, 733353337, 1193100992213191, 1193120192093911, 1193900112293191, 1193902910213911, 1733922710213719, 1933913317893391, 1933983337193191, 3191100999231193, 3191949710331913, 3371722912019173 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Subsequence of A224164, in which only the main diagonal is requested to be a reversible prime. Suggested by Charles R Greathouse IV.
The smallest terms with 4, 9, 16, 25 and 36 digits are 1117, 179991179, 1193100992213191, 1119710007705077000179111 and 111119100049100049928141172283919913.
LINKS
EXAMPLE
When the digits of the prime p = 3391382115599173 are arranged in a 4 X 4 matrix:
3391
3821
1559
9173
the rows, the columns and the two main diagonals are 4 digits reversible primes, so p is in the sequence.
CROSSREFS
Cf. A224164.
Sequence in context: A050665 A090721 A224164 * A066306 A212667 A252357
KEYWORD
nonn,base
AUTHOR
Giovanni Resta, Apr 05 2013
STATUS
approved

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Last modified March 29 08:59 EDT 2024. Contains 371268 sequences. (Running on oeis4.)