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 A056025 #30 Apr 08 2025 15:43:41
%S A056025 1,19,22,23,70,80,89,99,146,147,150,168,170,188,191,192,239,249,258,
%T A056025 268,315,316,319,337,339,357,360,361,408,418,427,437,484,485,488,506,
%U A056025 508,526,529,530,577,587,596,606,653,654,657,675,677,695,698,699,746
%N A056025 Numbers k such that k^12 == 1 (mod 13^2).
%C A056025 From 19 to 168 inclusive, these are the numbers that 'fool' the strong pseudoprimality test described in Wilf (1986) in regard to determining whether 169 is composite. - _Alonso del Arte_, Feb 05 2012
%D A056025 Herbert S. Wilf, Algorithms and Complexity, Englewood Cliffs, New Jersey: Prentice-Hall, 1986, pp. 158-160.
%H A056025 Amiram Eldar, <a href="/A056025/b056025.txt">Table of n, a(n) for n = 1..10000</a>
%H A056025 <a href="/index/Rec#order_13">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,0,0,0,0,0,0,0,0,1,-1).
%F A056025 From _Mike Sheppard_, Feb 19 2025 : (Start)
%F A056025 a(n) = a(n-1) + a(n-12) - a(n-13).
%F A056025 a(n) = a(n-12) + 13^2.
%F A056025 a(n) ~ (13^2/12)*n. (End)
%t A056025 Select[ Range[ 800 ], PowerMod[ #, 12, 169 ]==1& ]
%t A056025 LinearRecurrence[{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1}, {1, 19, 22, 23, 70, 80, 89, 99, 146, 147, 150, 168, 170}, 56] (* _Mike Sheppard_, Feb 19 2025 *)
%o A056025 (PARI) is(k)=Mod(k,169)^12==1 \\ _Charles R Greathouse IV_, Feb 07 2018
%Y A056025 Cf. A056021, A056022, A056024, A056026, A056027, A056028, A056031, A056034, A056035.
%Y A056025 Cf. A381319 (general case mod n^2).
%K A056025 nonn,easy
%O A056025 1,2
%A A056025 _Robert G. Wilson v_, Jun 08 2000
%E A056025 Definition corrected by _T. D. Noe_, Aug 23 2008