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.

A378632 Numbers that set records in A378181.

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%I A378632 #6 Dec 06 2024 11:10:06
%S A378632 1,4,6,12,24,48,60,96,120,240,420,480,840,1680,3360,6720,13440,18480,
%T A378632 26880,36960,53760,73920,147840,295680,480480,591360,960960,1182720,
%U A378632 1921920,3843840,7687680,15375360,30750720,61501440,65345280,123002880,130690560,246005760
%N A378632 Numbers that set records in A378181.
%C A378632 Numbers n that set records for binomial(bigomega(n)+omega(n)-1, omega(n)), where bigomega = A001222 and omega = A001221.
%C A378632 a(n) is of the form 2^k * P(i), k >= 0, where primorial P = A002110.
%C A378632 Proper subset of A070175.
%H A378632 Michael De Vlieger, <a href="/A378632/b378632.txt">Table of n, a(n) for n = 1..10000</a>
%t A378632 f[x_] := Block[{i, k, m, nn, p}, nn = Product[Prime[j], {j, x}]; Set[{k, i, p}, Range[0, 2]]; {1}~Join~Union@ Reap[Until[i > x, While[Set[m, 2^k*p] <= nn, Sow[m]; k++]; k = 0; i++; p *= Prime[i] ] ][[-1, 1]] ] (* generate A070175 *);
%t A378632 r = 0; Reap[Do[If[# > r, r = #; Sow[n]] &@ Binomial[#2 + #1 - 1, #1] & @@ {PrimeNu[n], PrimeOmega[n]}, {n, f[10]}] ][[-1, 1]]
%Y A378632 Cf. A000079, A001221, A001222, A002110, A007947, A070175, A378181.
%K A378632 nonn,easy
%O A378632 1,2
%A A378632 _Michael De Vlieger_, Dec 02 2024