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.

A054481 Highest common factor of successive highly composite numbers (1), A002182.

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%I A054481 #22 Sep 29 2015 09:10:32
%S A054481 1,2,2,6,12,12,12,12,60,60,60,120,360,120,420,420,840,2520,2520,2520,
%T A054481 5040,5040,5040,2520,2520,5040,5040,27720,27720,55440,55440,55440,
%U A054481 55440,166320,55440,110880,55440,360360,360360
%N A054481 Highest common factor of successive highly composite numbers (1), A002182.
%C A054481 Not the same as the first differences of A002182. The latter are given by A262501, which differs from this sequence for the first time at n=25, where A262501(25) = 17640, while here the 25th term a(26) is 2520. The sequences differ next time at positions n = 52, 53, 54, 64, 67, 82, 83, 84, 85, 86, 87, 88, 90, 91, 96, 100, 106, ... (when one-based indexing as in A262501 is used). - _Antti Karttunen_, Sep 24 2015
%H A054481 Antti Karttunen, <a href="/A054481/b054481.txt">Table of n, a(n) for n = 2..1000</a> (computed from the b-file of A002182 provided by _T. D. Noe_)
%F A054481 a(n) = GCD(A002182(n-1), A002182(n)) = A002182(n)/A054483(n) = A002182(n-1)/A054482(n).
%e A054481 a(7)=12 because A002182(7)=36, A002182(6)=24 and GCD(36,24)=12.
%Y A054481 Cf. A002182, A054482, A054483, A262501.
%K A054481 easy,nonn
%O A054481 2,2
%A A054481 _Henry Bottomley_, Mar 31 2000
%E A054481 Erroneous comment (wrong interpretation) removed by _Antti Karttunen_, Sep 25 2015