# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a079451 Showing 1-1 of 1 %I A079451 #29 Sep 08 2022 08:45:08 %S A079451 2,0,3,2,7,11,3,29,47,19,41,199,23,521,281,31,2207,3571,107,9349,2161, %T A079451 211,307,461,1103,151,90481,5779,14503,19489,2521,3010349,4481,9901, %U A079451 63443,911,103681,54018521,29134601,859,3041,370248451,1427,144481,967,541 %N A079451 Highest prime dividing the n-th Lucas number (A000032); 0 when no such prime exists. %H A079451 Amiram Eldar, Table of n, a(n) for n = 0..1000 (using Blair Kelly's data) %H A079451 J. Brillhart, P. L. Montgomery and R. D. Silverman, Tables of Fibonacci and Lucas factorizations, Math. Comp. 50 (1988), 251-260, S1-S15. Math. Rev. 89h:11002. %H A079451 Blair Kelly, Factorizations of first 1000 Lucas numbers. %F A079451 a(n) = A006530(A000032(n)). - _Felix Fröhlich_, Dec 26 2016 %p A079451 A079451 := proc(n) %p A079451 if n = 1 then %p A079451 0; %p A079451 else %p A079451 A006530(A000032(n)) ; %p A079451 end if; %p A079451 end proc: %p A079451 seq(A079451(n),n=0..30) ; # _R. J. Mathar_, Oct 26 2013 %t A079451 Join[{2,0},f[n_]:=(FactorInteger@LucasL@n)[[-1,1]];Array[f,60,2]] (* _Vincenzo Librandi_, Dec 26 2016 *) %o A079451 (PARI) a(n) = my(f = factor(fibonacci(n+1)+fibonacci(n-1))); if (om = #f~, f[om, 1], 0); \\ _Michel Marcus_, Oct 26 2013 %o A079451 (Magma) [2,0] cat [Maximum(PrimeDivisors(Lucas(n))): n in [2..60]]; // _Vincenzo Librandi_, Dec 26 2016 %Y A079451 Cf. A000032, A006530. %K A079451 nonn %O A079451 0,1 %A A079451 _Lekraj Beedassy_, Jan 13 2003 %E A079451 More terms from _Michel Marcus_, Oct 26 2013 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE