cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A375234 Square array T(n,k), n>1 and k>1, read by antidiagonals in ascending order, giving the smallest n*k-digit number that, if arranged in an n X k matrix, forms a k-digit emirp (A006567) in each row and an n-digit emirp in each column, or -1 if no such number exists.

Original entry on oeis.org

1331, 131337, 113337, 13139731, 113113337, 11933371, 1313717979, 113149971311, 119314713911, 1119737379, 131313131397, 113107709179991, 1193100990013911, 111971414339313, 111119333337
Offset: 2

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Author

Jean-Marc Rebert, Aug 06 2024

Keywords

Examples

			T(3,2) = 131337 is the smallest 3*2-digit that if arranged in a 3 X 2 matrix yields in each row and column an emirp, i.e.,
 13
 13
 37
-> 13 (2 times), 37 (1 times), 113 (1 time), 337 (1 time) are all emirps.
Table begins (upper left corner = T(2,2)):
      1331       113337         11933371 ...
    131337    113113337     119314713911 ...
  13139731 113149971311 1193100990013911 ...
       ...          ...              ... ...
		

Crossrefs