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 A181489 Composite Flavius' numbers (A000960) whose prime factors are again Flavius' numbers. 1
 27, 39, 49, 63, 91, 133, 147, 399, 567, 763, 2187, 13239, 15379, 15883, 21207, 32761, 151599, 173563, 180739, 268423, 746607, 2277163, 2557359, 3114783, 8218083, 28604419, 65002743, 68944959, 91727883, 93742347, 237963999, 310488507 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Contains A181488 as a subsequence. LINKS Klaus Brockhaus, Table of n, a(n) for n = 1..50 PROG (PARI) A181489(Nmax) = { my(S=[]); for(n=2, Nmax, my(F=n); for(i=1, n-1, F=(n-i)*ceil(F/(n-i)+1)); S=setunion(S, Set(F)); isprime(F) & next; for(i=1, #F=factor(F)~, setsearch(S, F[1, i])|next(2)); print1(factorback(F~), ", "))} CROSSREFS Sequence in context: A159259 A097228 A039614 * A117103 A217008 A124940 Adjacent sequences:  A181486 A181487 A181488 * A181490 A181491 A181492 KEYWORD nonn AUTHOR M. F. Hasler, Oct 29 2010 EXTENSIONS a(22)-a(32) from Donovan Johnson and Klaus Brockhaus, Oct 30 2010 STATUS approved

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