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 A375640 #13 Aug 23 2024 10:46:33 %S A375640 1,6,6,6,3181503,213118335,21363375160,83495980981,595814595900153, %T A375640 2153650189195351,49340595918273751,3380756271799042653, %U A375640 13175529217290940503 %N A375640 The smallest triangular number that begins a run of at least n consecutive triangular numbers with the same number of divisors. %e A375640 a(4) = 6 because 6 is the smallest triangular number that begins a run of 4 consecutive triangular numbers (6, 10, 15, 21) with the same number of divisors, i.e. 4. %e A375640 a(5) = 3181503 because 3181503 is the smallest triangular number that begins a run of 5 consecutive triangular numbers (3181503, 3184026, 3186550, 3189075, 3191601) with the same number of divisors, i.e. 24. %Y A375640 Cf. A000217, A063440, A319037, A319038. %K A375640 nonn,more,hard %O A375640 1,2 %A A375640 _Shyam Sunder Gupta_, Aug 22 2024