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%I #19 Mar 09 2014 12:56:57
%S 1,3,4,6,8,6,8,8,12,12,12,12,16,12,16,24,14,24,16,18,24,24,18,32,24,
%T 20,28,24,24,24,36,24,32,48,30,36,28,36,48,32,40,30,36,32,48,48,56,36,
%U 36,48,40,48,38,60,40,72,42,48,72,42,48,72,44,60,48,54,84
%N Write the n-th nonprime (A018252(n)) as a product of primes; increase one copy of the largest prime by 1 and decrease one copy of the smallest prime by 1, multiply the resulting numbers.
%e 1st nonprime = 1 (has no prime factors); a(1) = empty product = 1.
%e 2nd nonprime = 4 = (p(max)=2)*(p(min)=2); a(2) = (2+1)*(2-1) = 3*1 = 3.
%e 3rd nonprime = 6 = (p(max)=3)*(p(min)=2); a(3) = (3+1)*(2-1) = 4*1 = 4.
%e 4th nonprime = 8 = (p(max)=2)*(p=2)*(p(min)=2); a(4) = (2+1)*2*(2-1) = 3*2*1 = 6.
%K nonn
%O 1,2
%A _Juri-Stepan Gerasimov_, Aug 07 2008
%E Three terms corrected by _R. J. Mathar_, Aug 18 2008
%E Entry revised by _Jon E. Schoenfield_, Mar 09 2014, following revision of A141218 by _N. J. A. Sloane_
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