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 A358544 #21 Feb 16 2025 08:34:04
%S A358544 1,4,20,320,460,5440,14260,12920,168640,103360,594320,3878720,2377280,
%T A358544 9211960,18423920,36847840,125995840,73695680,865924240,976467760,
%U A358544 1952935520,3463696960,3905871040,31246968320,22946992360
%N A358544 a(n) is the smallest number with exactly n divisors that are centered triangular numbers.
%C A358544 Any subsequent terms are > 10^10. - _Lucas A. Brown_, Dec 24 2022
%H A358544 Lucas A. Brown, <a href="https://github.com/lucasaugustus/oeis/blob/main/figuratedivisors.py">Python program</a>.
%H A358544 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/CenteredTriangularNumber.html">Centered Triangular Number</a>
%H A358544 <a href="/index/Di#divisors">Index entries for sequences related to divisors of numbers</a>
%e A358544 a(3) = 20 because 20 has 3 centered triangular divisors {1, 4, 10} and this is the smallest such number.
%o A358544 (PARI) isct(n) = my(k=(2*n-2)/3, m); (n==1) || ((denominator(k)==1) && (m=sqrtint(k)) && (m*(m+1)==k)); \\ A005448
%o A358544 a(n) = my(k=1); while (sumdiv(k, d, isct(d)) != n, k++); k; \\ _Michel Marcus_, Nov 21 2022
%Y A358544 Cf. A005179, A005448, A130317, A300409, A358542, A358545.
%K A358544 nonn,more
%O A358544 1,2
%A A358544 _Ilya Gutkovskiy_, Nov 21 2022
%E A358544 a(14) from _Michel Marcus_, Nov 21 2022
%E A358544 a(15)-a(25) from _Jinyuan Wang_, Nov 29 2022