

A238338


Encoded bases for which A214424(n) is palindromic.


3



13, 26, 13, 47, 28, 46, 24, 17, 25, 14, 19, 47, 17, 34, 68, 13, 24, 46, 45, 17, 46, 28, 49, 28, 56, 14, 45, 19, 45, 37, 16, 48, 59, 46, 14, 18, 15, 56, 59, 26, 36, 29, 25, 37, 69, 28, 28, 56, 47, 68, 58, 29, 35, 17, 78, 48, 49, 68, 19, 27, 79, 46, 59, 37, 28, 17
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OFFSET

1,1


COMMENTS

The two bases b < c are encoded as one number (b1)*10 + (c1). Similar to A214427 which tabulates the single base for which A214423(n) is palindromic. In the first 1000 terms, the base pairs (2,4), (2,8), (3,9), and (4,8) are most common, occurring 148, 227, 166, and 94 times, respectively. The base pair (2,3) occurs only once.


LINKS

T. D. Noe and Giovanni Resta, Table of n, a(n) for n = 1..10000 (first 1000 terms from T. D. Noe)
Attila Bérczes and Volker Ziegler, On simultaneous palindromes, arXiv 1403.0787, Mar 04 2014
Edray Herber Goins, Palindromes in different bases: a conjecture of J. Ernest Wilkins, Integers, Vol. 9 (2009), A55


MATHEMATICA

n = 1; t = {}; While[Length[t] < 100, n++; If[Count[c = Table[s = IntegerDigits[n, m]; s == Reverse[s], {m, 2, 10}], True] == 2, d = Flatten[Position[c, True]]; AppendTo[t, 10*d[[1]] + d[[2]]]]]; t


CROSSREFS

Cf. A214423, A214424, A214427.
Sequence in context: A123827 A105796 A226051 * A040156 A296752 A297279
Adjacent sequences: A238335 A238336 A238337 * A238339 A238340 A238341


KEYWORD

nonn,base


AUTHOR

T. D. Noe, Mar 07 2014


STATUS

approved



