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%I #16 Jan 01 2017 15:46:16
%S 2,72,2311920,2562840000,3844062000,10617344640,39923436672,
%T 49213207440,72555078960,215073801360,476873804160,719511945840,
%U 972291644352,1567905917760,2012086928880,4707721763712,7251605387280
%N Products of pairs of consecutive refactorable numbers.
%C The product of a pair of consecutive refactorable numbers is itself refactorable.
%H S. Colton, <a href="http://www.cs.uwaterloo.ca/journals/JIS/colton/joisol.html">Refactorable Numbers - A Machine Invention</a>, J. Integer Sequences, Vol. 2, 1999, #2.
%H S. Colton, <a href="http://web.archive.org/web/20070831060523/http://www.dai.ed.ac.uk/homes/simonco/research/hr/">HR - Automatic Theory Formation in Pure Mathematics</a>
%F a(n) = A036898(2n) * A036898(2n+1). - _Michel Marcus_, Aug 31 2013
%e 8 and 9 are consecutive refactorable numbers, so 8*9 = 72 is in the sequence.
%o (PARI) isrefac(n) = ! (n % numdiv(n));
%o lista(nn) = {for (n=1, nn, if (isrefac(n) && isrefac(n+1), print1(n*(n+1) ", ")););} \\ _Michel Marcus_, Aug 31 2013
%Y Cf. A033950.
%K nonn
%O 1,1
%A Simon Colton (simonco(AT)cs.york.ac.uk)
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