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 A278474 #8 Feb 16 2025 08:33:37
%S A278474 24,36,76,375,376,432,624,625,693,875,999,2499,4557,8307,9375,9376,
%T A278474 9999,34375,40625,47943,50001,59375,81249,90624,90625,99999,109376,
%U A278474 186432,218751,586432,609375,690624,718751,781249,890625,954193,968751,999999,2109375,2890624,2890625
%N A278474 Numbers n such that the product of proper divisors of n ends with n and n is not a multiplicatively perfect number (A007422).
%C A278474 Numbers n such that A007956(n) == n (mod A011557(A055642(n))) and A000005(n) <> 4.
%H A278474 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/DivisorProduct.html">Divisor Product</a>
%H A278474 <a href="/index/Ar#automorphic">Index entries for sequences related to automorphic numbers</a>
%H A278474 <a href="/index/Fi#final">Index entries for sequences related to final digits of numbers</a>
%e A278474 24 is in the sequence because 24 has 7 proper divisors {1,2,3,4,6,8,12} and 1*2*3*4*6*8*12 = 13824;
%e A278474 36 is in the sequence because 36 has 8 proper divisors {1,2,3,4,6,9,12,18} and 1*2*3*4*6*9*12*18 = 279936;
%e A278474 76 is in the sequence because 76 has 5 proper divisors {1,2,4,19,38} and 1*2*4*19*38 = 5776, etc.
%t A278474 Select[Range[3000000], Mod[Sqrt[#1]^DivisorSigma[0, #1]/#1, 10^IntegerLength[#1]] == #1 && Sqrt[#1]^DivisorSigma[0, #1] != #1^2 & ]
%Y A278474 Cf. A000005, A007422, A007956, A011557, A055642, A210994
%K A278474 nonn,base
%O A278474 1,1
%A A278474 _Ilya Gutkovskiy_, Nov 23 2016