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 A270493 #29 Mar 09 2024 11:01:27 %S A270493 3,10,45,1710,308961,601929,732202,2214702,7626372,13976550,21971144, %T A270493 27575700,207268867,1014593260,1134331652,3140421935,6196934304, %U A270493 21338685403,49990179304,82456321500 %N A270493 Integers n such that the n-th prime divides the n-th Pell number (A000129(n)). %C A270493 For a(5), corresponding Pell number A000129(308961) has 118263 digits. %C A270493 Any subsequent terms exceed 2*10^11. - _Lucas A. Brown_, Mar 08 2024 %H A270493 Lucas A. Brown, <a href="https://github.com/lucasaugustus/oeis/blob/main/A270493.py">Python program</a>. %e A270493 10 is a term because A000129(10) = 2378, A000040(10) = 29 and 2378 mod 29 = 0. %t A270493 Select[Range[1, 10000], Divisible[Fibonacci[#, 2], Prime[#]] &] (* _Vaclav Kotesovec_, Mar 18 2016 *) %o A270493 (PARI) a000129(n) = ([2, 1; 1, 0]^n)[2, 1]; %o A270493 for(n=1, 1e10, if(lift(Mod(a000129(n), prime(n))) == 0, print1(n, ", "))); %o A270493 (Python) # See LINKS. %Y A270493 Cf. A000040, A000129, A075702. %K A270493 nonn,more,hard %O A270493 1,1 %A A270493 _Altug Alkan_, Mar 18 2016 %E A270493 a(6)-a(8) from _Gheorghe Coserea_, Mar 24 2016 %E A270493 a(9)-a(13) from _Daniel Suteu_, Nov 07 2019 %E A270493 a(14)-a(20) from _Lucas A. Brown_, Mar 08 2024