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 A076518 #6 Nov 27 2016 02:34:07 %S A076518 1,2,4,11,19,29,31,41,59,61,71,79,89,101,109,120,131,139,149,151,179, %T A076518 181,191,199,211,229,239,241,251,269,271,281,311,331,348,349,359,379, %U A076518 389,401,409,419,421,431,439,449,461,479,491,499,509,521,541,569,571 %N A076518 Numbers n such that Fibonacci(n) == sigma(n) (mod n). %C A076518 It appears that most of the terms of this sequence satisfy Fibonacci(n) == 1 (mod n). Also it seems that most of the terms are primes. %H A076518 Charles R Greathouse IV, <a href="/A076518/b076518.txt">Table of n, a(n) for n = 1..10000</a> %t A076518 Select[Range[10^4], Mod[Fibonacci[ # ], # ] == Mod[DivisorSigma[1, # ], # ] &] %o A076518 (PARI) fibmod(n, m)=((Mod([1, 1; 1, 0], m))^n)[1, 2] %o A076518 is(n)=fibmod(n,n)==sigma(n) \\ _Charles R Greathouse IV_, Nov 27 2016 %K A076518 nonn %O A076518 1,2 %A A076518 _Joseph L. Pe_, Oct 17 2002