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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.

A296580 Odd primes p such that tau(p) is congruent to (p-1)/2 (mod p), where tau is the Ramanujan tau function (A000594).

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%I A296580 #17 Feb 16 2025 08:33:52
%S A296580 191,5399,1259393
%N A296580 Odd primes p such that tau(p) is congruent to (p-1)/2 (mod p), where tau is the Ramanujan tau function (A000594).
%C A296580 a(4) > 10^7.
%C A296580 There is no odd prime p (< 10^7) such that tau(p) is congruent to (p+1)/2 (mod p).
%H A296580 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/TauFunction.html">Tau Function.</a>
%H A296580 Wikipedia, <a href="https://en.wikipedia.org/wiki/Ramanujan_tau_function">Ramanujan tau function</a>
%e A296580 tau(191) = 2762403350592 and 2762403350592 == 95 mod 191, so a(1) = 191.
%e A296580 tau(5399) = -616400667743946780600 and -616400667743946780600 == 2699 mod 5399, so a(2) = 5399.
%e A296580 tau(1259393) = -600367974333827988240021654527358 and -600367974333827988240021654527358 == 629696 mod 1259393, so a(3) = 1259393.
%Y A296580 Cf. A000594, A007659, A076847 (tau(p)), A193855, A273650, A273651, A295645.
%K A296580 nonn,more
%O A296580 1,1
%A A296580 _Seiichi Manyama_, Dec 16 2017