cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A200381 Products of Lucas numbers.

This page as a plain text file.
%I A200381 #21 Aug 03 2014 14:01:36
%S A200381 1,2,3,4,6,7,8,9,11,12,14,16,18,21,22,24,27,28,29,32,33,36,42,44,47,
%T A200381 48,49,54,56,58,63,64,66,72,76,77,81,84,87,88,94,96,98,99,108,112,116,
%U A200381 121,123,126,128,132,141,144,147,152,154,162,168,174,176,188
%N A200381 Products of Lucas numbers.
%C A200381 Complement of A200995.
%C A200381 Contains A000032, A001254, A075155, A099923, A103325 .. and any products of their members.
%H A200381 T. D. Noe, <a href="/A200381/b200381.txt">Table of n, a(n) for n = 1..1099</a>
%H A200381 <a href="/index/Lu#Lucas">Index entries for Lucas sequences</a>
%e A200381 Contains 9=3^2, 14=2*7, 21=3*7, 27=3^3, 42=2*3*7, 141 =3*47 etc.
%t A200381 lim = 11; luc = LucasL[Range[0, lim]]; luc = Delete[luc, 2]; last = luc[[-1]]; t = {1}; Do[t2 = luc[[n]]^Range[Floor[Log[last]/Log[luc[[n]]]]]; s = Select[Union[Flatten[Outer[Times, t, t2]]], # <= last &];  t = Union[t, s], {n, lim}]; t (* _T. D. Noe_, Nov 17 2011 *)
%Y A200381 Cf. A000032, A181156. Complement of A200995.
%K A200381 nonn
%O A200381 1,2
%A A200381 _R. J. Mathar_, Nov 17 2011