References to A175424

a(n) = number of steps of iterations of {(((D_k^D_(k-1))^D_(k-2))^...)^D_1, where D_k = k-th digit D of number r and k = the number digit of number r in decimal expansion of r (A055642)} needed to reach a single-digit number starting at r = n, or a(n) = -1 if a single-digit number is never reached.
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 3, 3, 2, 1, 1, 1


1 seqfan posts

Sun Nov 14 22:42:15 CET 2010    [seqfan] OEIS: what went wrong

Index of A-numbers in seqfan: by ascending order    by month    by frequency    by keyword
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