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A261170 Number of decimal digits of A260871(n), where A260871 lists primes whose base-b representation is the concatenation of the base-b representations of (1, 2, ..., k, k-1, ..., 1).

%I A261170 #10 Jun 29 2019 11:23:03
%S A261170 2,3,4,5,7,9,17,20,31,38,43,64,64,70,91,93,102,117,120,123,127,127,
%T A261170 127,136,160,166,176,235,321,351,353,389,403,418,418,421,422,466,542,
%U A261170 578,579,703,706,725,731,765,780,792,795,799,803,839,840,848,849,863
%N A261170 Number of decimal digits of A260871(n), where A260871 lists primes whose base-b representation is the concatenation of the base-b representations of (1, 2, ..., k, k-1, ..., 1).
%C A261170 Larger values based on computations by D. Broadhurst, cf. data file in A260871.
%C A261170 See A261171 and A261172 for the k- and b-values such that A260871(n) = A[b](k), where the sequences A[b] of numbers whose base-b representation is the concatenation of the base-b representations of (1, 2, ..., k, k-1, ..., 1) are listed in A173427, A260853 - A260859, A173426, A260861 - A260866 and A260860 for bases b=2, ..., b=16 and b=60.
%H A261170 M. F. Hasler, <a href="/A261170/b261170.txt">Table of n, a(n) for n = 1..434</a>
%K A261170 nonn,base,hard
%O A261170 1,1
%A A261170 _M. F. Hasler_, Sep 15 2015