cp's OEIS Frontend

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.

A302934 Highly composite deficient numbers: deficient numbers k whose number of divisors d(k) > d(m) for all deficient numbers m < k.

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%I A302934 #12 Jul 21 2021 00:44:24
%S A302934 1,2,4,8,16,32,64,105,225,315,1155,2475,4455,8775,26325,27027,63063,
%T A302934 106029,247401,693693,829521,969969,2241603,3741309,7894341,8083075,
%U A302934 32569173,33671781,37182145,56581525,146791359,185910725,622396775,929553625,1301375075
%N A302934 Highly composite deficient numbers: deficient numbers k whose number of divisors d(k) > d(m) for all deficient numbers m < k.
%C A302934 The record numbers of divisors are 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 16, 18, 20, 24, 30, 32, 36, 40, 48, 54, 60, 64, 72, 80, 84, 96, 108, 112, 128, 144, 160, 192, 216, 256, 288, ...
%t A302934 a={}; dm=0; Do[ If[DivisorSigma[1,n]>=2n, Continue[]]; d=DivisorSigma[0,n]; If[d>dm, dm=d; AppendTo[a,n]], {n,1,1000000}]; a
%o A302934 (PARI) lista(nn) = {my(maxd = 0); for (n=1, nn, if ((sigma(n) < 2*n) && (numdiv(n) > maxd), maxd = numdiv(n); print1(n, ", ");););} \\ _Michel Marcus_, Apr 17 2018
%Y A302934 Cf. A000005, A002182, A005100.
%K A302934 nonn
%O A302934 1,2
%A A302934 _Amiram Eldar_, Apr 16 2018