%I A140332
%S A140332 0,1,2,3,4,5,6,7,8,9,10,11,12,14,15,16,18,20,21,22,24,25,27,28,30,32,33,
%T A140332 35,36,40,42,44,45,48,49,54,55,56,63,64,66,72,77,80,81,88,96,99,101,110,
%U A140332 111,112,121,128,131,132,141,144,151,154,160,161,165,171,176,181,191
%N A140332 Products of two palindromes in base 10.
%C A140332 Genevieve Paquin, p. 5: "Lemma 3.7: a Christoffel word can always be
written as the product of two palindromes." Products of two palindromes
in base 10 may be either a palindrome (i.e. 202 * 202 = 40804} or
a nonpalindrome (i.e. 2 * 88 = 176, or 22 * 33 = 726}. Contains A115683
as a proper subset. The nonpalindromes in this sequence are the same
as the nonnpalindroms in A115683: {10, 12, 14, 15, 16, 18, 20, 21,
24, 25, 27, 28, 30, 32, 35, 36, 40, 42, 45, 48, 49, 54, 56, 63, 64,
72, 81, 110, 132, 154, 165, 176, 198, 220, 231, 264, 275, 297, 302,
308, 322, 330...} which is not yet a sequence in OEIS.
%H A140332 Genevieve Paquin, <a href="http://arXiv.org/pdf/0805.4174">On a generalization
of Christoffel words: epichristoffel words</a>, May 27, 2008.
%F A140332 {i*j such that i is in A002113 and j is in A002113} = A002113 UNION A115683.
%Y A140332 Cf. A002113, A115683.
%Y A140332 Sequence in context: A033637 A084347 A051038 this_sequence A155182 A096076
A108864
%Y A140332 Adjacent sequences: A140329 A140330 A140331 this_sequence A140333 A140334
A140335
%K A140332 easy,nonn,base
%O A140332 1,3
%A A140332 Jonathan Vos Post (jvospost3(AT)gmail.com), May 28 2008
|