Search: id:A086598 Results 1-1 of 1 results found. %I A086598 %S A086598 0,1,1,1,1,2,1,1,2,2,1,3,1,2,3,1,1,3,1,2,3,3,2,3,3,2,3,2,2,4,1,2,3,3,4, %T A086598 4,1,2,4,3,1,5,2,4,6,3,1,4,2,4,4,3,1,4,4,2,4,3,3,6,1,2,6,2,5,5,2,2,5,4, %U A086598 1,4,2,3,7,2,4,4,1,2,5,4,2,6,4,2,5,3,2,6,3,3,4,4,5,4,2,4,7,4,3,6,3,4,9 %N A086598 Number of distinct prime factors in Lucas(n). %C A086598 Interestingly, the Lucas numbers separate the primes into three disjoint sets: (A053028) primes that do not divide any Lucas number, (A053027) primes that divide Lucas numbers of even index and (A053032) primes that divide Lucas numbers of odd index. %H A086598 T. D. Noe, Table of n, a(n) for n=1..1000 (using Blair Kelly's data) %H A086598 Blair Kelly, Fibonacci and Lucas Factorizations %H A086598 Eric Weisstein's World of Mathematics, Lucas Number %F A086598 a(n) = Sum{d|n and n/d odd} A086600(d) + 1 if 6|n, a Mobius-like transform %t A086598 Lucas[n_] := Fibonacci[n+1] + Fibonacci[n-1]; Table[Length[FactorInteger[Lucas[n]]], {n, 150}] %Y A086598 Cf. A000204 (Lucas numbers), A086599 (number of prime factors, counting multiplicity), A086600 (number of primitive prime factors). %Y A086598 Cf. A053027, A053028, A053032. %Y A086598 Sequence in context: A035170 A111949 A143323 this_sequence A074746 A133188 A008612 %Y A086598 Adjacent sequences: A086595 A086596 A086597 this_sequence A086599 A086600 A086601 %K A086598 hard,nonn %O A086598 1,6 %A A086598 T. D. Noe (noe(AT)sspectra.com), Jul 24 2003 Search completed in 0.001 seconds