# Checkerboard

Algebra Level pending

A checkerboard of $$13$$ rows and $$17$$ columns has a number written in each square, beginning in the upper left corner, so that the first row is numbered $$1,2,\ldots,17$$, the second row $$18,19,\ldots,34$$, and so on down the board. If the board is renumbered so that the left column, top to bottom, is $$1,2,\ldots,13$$, the second column $$14,15,\ldots,26$$ and so on across the board, some squares have the same numbers in both numbering systems. Find the sum of the numbers in these squares (under either system).

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