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 A129499 #9 Feb 16 2025 08:33:05
%S A129499 30,210,330,390,510,570,690,870,930,1110,1230,1290,1410,1470,1590,
%T A129499 1770,1830,2010,2130,2190,2310,2730,3570,3990,4830,5610,6090,6510,
%U A129499 7590,7770,8610,9030,9870,11130,12390,12810,14070,14910,15330,16590,17430,18690
%N A129499 Records for unitary abundant numbers, i.e., those integers which set a record for having a greater unitary abundance than any of their predecessors.
%H A129499 Amiram Eldar, <a href="/A129499/b129499.txt">Table of n, a(n) for n = 1..750</a>
%H A129499 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/UnitaryDivisor.html">Unitary Divisor</a>.
%F A129499 Values of A034683 corresponding to those positions in A129498 at which records occur.
%e A129499 A129498 begins 12, 12, 12, 4, 12, 12, 12, 12, 12, 12, 12, 156, 12, 12. The second record value is 156, which occurs at position 12. As A034683(12)=210, it follows that a(2)=210.
%t A129499 UnitaryDivisors[n_Integer?Positive]:=Select[Divisors[n],GCD[ #,n/# ]==1&];sstar[n_]:=Plus@@UnitaryDivisors[n]-n;RunningMaxima[l_]:=Rest[FoldList[Max,-Infinity,l]] HighWaterMarks[l_]:=Module[{s=Split[RunningMaxima[l]]}, {First/@s,Most[FoldList[Plus,1,Length/@s]]} ];data1=Select[Range[20000],sstar[ # ]-#>0 &];data2=sstar[ # ]-# &/@data1;pos=Last[HighWaterMarks[data2]];champs=data1[[ # ]] &/@pos
%Y A129499 Cf. A034448, A034460, A034683, A129468, A129498.
%K A129499 easy,nonn
%O A129499 1,1
%A A129499 _Ant King_, Apr 20 2007