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Search: id:A144855
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| A144855 |
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Number of paths from (1,1) to (n,n) in an n X n grid using only the steps +(1,0), -(1,0), +(0,1) and -(0,1) which do not self-intersect and which avoid any point (p,q) satisfying "(p-1)*n + q is prime". |
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+0
1
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| 1, 0, 0, 0, 0, 0, 0, 254, 0, 0, 0, 0, 0
(list; graph; listen)
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OFFSET
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1,8
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EXAMPLE
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One of the 254 prime avoiding paths for the n=8 case is 1,9,10,18,26,27,28,20,21,22,14,15,16,24,32,40,39,38,46,54,55,56,64
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CROSSREFS
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Sequence in context: A006060 A077695 A145628 this_sequence A110827 A062664 A158249
Adjacent sequences: A144852 A144853 A144854 this_sequence A144856 A144857 A144858
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KEYWORD
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hard,more,nonn
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AUTHOR
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Joseph E. Cooper III (easonrevant(AT)gmail.com), Sep 22 2008
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