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 A327713 #34 Aug 11 2025 07:19:58 %S A327713 6,26,60,65,70,81,96,126,135,141,175,176,196,205,206,226,305,310,330, %T A327713 340,346,371,380,435,436,440,460,480,481,516,595,611,646,650,665,666, %U A327713 685,696,700,710,716,725,730,736,745,751,760,765,775,780,811,826,841,860,871 %N A327713 Exceptional class of numbers k such that p(25*k + 24) == 0 (mod 125), where p() = A000041(). %C A327713 The unexceptional class consists of the numbers k == (2, 3, or 4) (mod 5). Watson (1938, p. 111) proved that such numbers k satisfy p(25*k + 24) == 0 (mod 125). %C A327713 (p(25*a(m) + 24)/125: m >= 1) = (3177000598, 140513239982045202108972, 23104937422373952975695974907848646058, ...). %H A327713 David A. Corneth, <a href="/A327713/b327713.txt">Table of n, a(n) for n = 1..10000</a> %H A327713 Watson, G. N., <a href="https://gdz.sub.uni-goettingen.de/id/PPN243919689_0179">Ramanujans Vermutung über Zerfällungsanzahlen</a>, J. Reine Angew. Math. (Crelle) 179 (1938), 97-128; see pp. 111-113. %e A327713 p(25*6 + 24) = p(174) = 397125074750 = 3177000598 * 125 (the only example in Watson (1938)). %o A327713 (PARI) is(n) = n % 5 < 2 && numbpart(25*n+24)%125==0 \\ _David A. Corneth_, Sep 23 2019 %Y A327713 Cf. A000041, A071734, A110375, A160524, A327714. %K A327713 nonn %O A327713 1,1 %A A327713 _Petros Hadjicostas_, Sep 23 2019 %E A327713 More terms from _David A. Corneth_, Sep 23 2019