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 A307845 #15 Aug 13 2025 07:17:23
%S A307845 1,4,36,576,14400,705600,57153600,6915585600,1168733966400,
%T A307845 337764116289600,121932845980545600,64502475523708622400,
%U A307845 40314047202317889000000,33904113697149344649000000,32581853262960520207689000000,44604557116992952164326241000000,74980260513665152588232411121000000
%N A307845 Exponential unitary highly composite numbers: where the number of exponential unitary divisors (A278908) increases to a record.
%C A307845 Subsequence of A025487.
%C A307845 All the terms have prime factors with multiplicities which are primorials > 1 (the primorials, A002110, are the unitary highly composite numbers), similarly to exponential highly composite numbers (A318278) whose prime factors have multiplicities which are highly composite numbers (A002182). Thus all the terms are squares. Their square roots are 1, 2, 6, 24, 120, 840, 7560, 83160, 1081080, 18378360, 349188840, 8031343320, 200783583000, 5822723907000, 180504441117000, ...
%C A307845 First differs from A306736 at n = 107. - _Georg Fischer_, Aug 13 2025
%H A307845 Amiram Eldar, <a href="/A307845/b307845.txt">Table of n, a(n) for n = 1..201</a>
%F A307845 A278908(a(n)) = 2^(n-1).
%t A307845 f[p_, e_] := 2^PrimeNu[e]; a[n_] := Times @@ (f @@@ FactorInteger[n]); s = {}; am = 0; Do[a1 = a[n]; If[a1 > am, am = a1; AppendTo[s, n]], {n, 1, 10^6}]; s
%Y A307845 Cf. A002110, A002182, A025487, A278908, A306736, A318278.
%K A307845 nonn
%O A307845 1,2
%A A307845 _Amiram Eldar_, May 01 2019