%I A020342
%S A020342 126,153,688,1206,1255,1260,1395,1435,1503,1530,1827,2187,3159,3784,6880,
%T A020342 10251,10255,10426,10521,10525,10575,11259,11439,11844,11848,12006,12060,
%U A020342 12384,12505,12546,12550,12595,12600,12762,12768,12798,12843,12955,12964
%N A020342 Vampire numbers (definition 1): n has a nontrivial factorization using
n's digits.
%C A020342 Nontrivial means that there must be at least two factors.
%D A020342 Clifford A. Pickover, A Passion for Mathematics, Wiley, 2005; see p.
65.
%e A020342 E.g. 1395 = 31*9*5.
%Y A020342 The following sequences are all closely related: A020342, A014575, A080718,
A048936, A144563.
%Y A020342 Sequence in context: A025388 A025389 A025380 this_sequence A009944 A104395
A109024
%Y A020342 Adjacent sequences: A020339 A020340 A020341 this_sequence A020343 A020344
A020345
%K A020342 nonn,base
%O A020342 1,1
%A A020342 David W. Wilson (davidwwilson(AT)comcast.net)
%E A020342 Edited by N. J. A. Sloane (njas(AT)research.att.com), Jan 03 2009
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