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 A056024 #23 Apr 07 2025 21:32:08
%S A056024 1,3,9,27,40,81,94,112,118,120,122,124,130,148,161,202,215,233,239,
%T A056024 241,243,245,251,269,282,323,336,354,360,362,364,366,372,390,403,444,
%U A056024 457,475,481,483,485,487,493,511,524,565,578,596,602,604,606,608,614,632
%N A056024 Numbers k such that k^10 == 1 (mod 11^2).
%H A056024 Amiram Eldar, <a href="/A056024/b056024.txt">Table of n, a(n) for n = 1..10000</a>
%H A056024 <a href="/index/Rec#order_11">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,0,0,0,0,0,0,1,-1).
%F A056024 From _Mike Sheppard_, Feb 19 2025: (Start)
%F A056024 a(n) = a(n-1) + a(n-10) - a(n-11).
%F A056024 a(n) = a(n-10) + 11^2.
%F A056024 a(n) ~ (11^2/10)*n. (End)
%t A056024 Select[ Range[ 800 ], PowerMod[ #, 10, 121 ]==1& ]
%t A056024 LinearRecurrence[{1, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1}, {1, 3, 9, 27, 40, 81, 94, 112, 118, 120, 122}, 65] (* _Mike Sheppard_, Feb 19 2025 *)
%Y A056024 Cf. A056021, A056022, A056025, A056026, A056027, A056028, A056031, A056034, A056035.
%Y A056024 Cf. A381319 (general case mod n^2).
%K A056024 nonn
%O A056024 1,2
%A A056024 _Robert G. Wilson v_, Jun 08 2000