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 A144855 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". 0
 1, 0, 0, 0, 0, 0, 0, 254, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,8 LINKS EXAMPLE 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 CROSSREFS Sequence in context: A243666 A243687 A263380 * A110827 A062664 A258696 Adjacent sequences:  A144852 A144853 A144854 * A144856 A144857 A144858 KEYWORD hard,more,nonn AUTHOR Joseph E. Cooper III (easonrevant(AT)gmail.com), Sep 22 2008 STATUS approved

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Last modified November 25 11:32 EST 2020. Contains 338623 sequences. (Running on oeis4.)