cp's OEIS Frontend

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.

A176946 Primes of the form 7^k+2^k.

This page as a plain text file.
%I A176946 #19 Aug 21 2025 00:04:04
%S A176946 2,53,2417
%N A176946 Primes of the form 7^k+2^k.
%C A176946 If 7^k+2^k is prime then k is either 0 or a power of 2. The corresponding values of k for a(1)-a(3) are 0, 2 and 4. If it exists, a(4) has k = 2^m with m > 19, and therefore it is larger than 7^(2^20) > 10^886149. - _Amiram Eldar_, Jul 17 2025
%o A176946 (Magma) [ a: k in [0..2100] | IsPrime(a) where a is 7^k+2^k ];
%Y A176946 Primes in A074602.
%K A176946 nonn,bref,hard,changed
%O A176946 1,1
%A A176946 _Vincenzo Librandi_, Apr 29 2010