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 A244666 #25 Sep 08 2022 08:46:08 %S A244666 1,2,3,9,21,33,81,261,897,1334,1364,2974,4364,14282,26937,46593,64665, %T A244666 74918,79833,92685,145215,147454,161001,162602,166934,289454,347738, %U A244666 383594,422073,430137,440013,443402,445874,621027,649154,655005,1174305,1187361,1670955 %N A244666 Numbers n such that floor(antisigma(n) / sigma(n)) = floor(antisigma(n+1) / sigma(n+1)). %C A244666 Also numbers n such that floor((n*(n+1)/2) / sigma(n)) = floor(((n+1)*(n+2)/2) / sigma(n+1)). %C A244666 Numbers n such that A244327(n) = A244327(n+1). %C A244666 Numbers n such that A244329(n) = A244329(n+1). %H A244666 Jaroslav Krizek, <a href="/A244666/b244666.txt">Table of n, a(n) for n = 1..39</a> %o A244666 (Magma) [n: n in [1..10^6] | Floor((n*(n+1)div 2) div (SumOfDivisors(n))) eq Floor(((n+1)*(n+2)div 2) div (SumOfDivisors(n+1)))] %Y A244666 Cf. A000203, A000217, A024816, A046022, A244327, A244328, A244329. %K A244666 nonn %O A244666 1,2 %A A244666 _Jaroslav Krizek_, Jul 08 2014