This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A072556 #17 Oct 14 2023 12:50:34 %S A072556 1,3,4,5,7,10,11,12,13,14,17,22,23,26,29,34,43,47,83,94,131,137,359, %T A072556 431,433,449,509,569,571 %N A072556 Numbers n such that n and the n-th Fibonacci number have the same number of distinct prime factors. %e A072556 a(7)=10 because 10 and 10th Fibonacci number(i.e. 55) have the same number of prime factors i.e. 2. - _Shyam Sunder Gupta_, Feb 05 2006 %p A072556 with(combinat): with(numtheory): a:=proc(n) if nops(factorset(fibonacci(n)))=nops(factorset(n)) then n else fi end: seq(a(n),n=1..150); # _Emeric Deutsch_, Apr 02 2006 %t A072556 Insert[Select[Range[1, 50], Length[FactorInteger[ # ]] ==Length[FactorInteger[Fibonacci[ # ]]] &], 2, 2] (* _Stefan Steinerberger_, Mar 20 2006 *) %t A072556 Select[Range[600],PrimeNu[#]==PrimeNu[Fibonacci[#]]&] (* _Harvey P. Dale_, Oct 14 2023 *) %Y A072556 Cf. A001221, A022307. %K A072556 more,nonn %O A072556 1,2 %A A072556 _Benoit Cloitre_, Aug 06 2002 %E A072556 More terms from _Sascha Kurz_, Jan 25 2003 %E A072556 Edited by _R. J. Mathar_, Aug 11 2008