A391870 - OEIS

%I #15 Dec 23 2025 03:06:15

%S 4,11,18,23,48,221,2003,2927,4256,10063,19296,23618,57576,70852,

%T 125558,181586,211101,593286,742861,1384104,1938665,2103883,2341224,

%U 2469308,2757948,3419961,4763217,8229111,9344114,13314161,14701551,20380851,22849565,31757205,34607267,46773074

%N Records in A210693.

%F a(n) = A210693(A391871(n)).

%t A210693[n_] := Module[{k = 0}, While[++k == n || PowerMod[n, k, 2*k + 1] != PowerMod[k, n, #]] & [2*n + 1]; k];

%t Module[{rec = 0}, Table[If[# > rec, rec = #, Nothing] & [A210693[m]], {m, 10000}]]

%Y Cf. A210693, A391871.

%K nonn

%O 1,1

%A _Paolo Xausa_, Dec 21 2025

%E a(27)-a(36) from _Michael S. Branicky_, Dec 22 2025