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%I #26 Mar 16 2022 02:50:13
%S 2048,30720,645120,7096320,92252160,1383782400,23524300800,
%T 446961715200,10280119449600,71960836147200,2086864248268800,
%U 64692791696332800,582235125266995200,21542699634878822400,883250685030031718400,37979779456291363891200,189898897281456819456000
%N a(1)=2048. For n>1, a(n) is the LCM of a(n-1) and A140635(a(n-1)).
%C Similar sequences starting with smaller powers of 2 are known to converge after a few terms.
%C This sequence is constant from n = 35. I.e.: a(n) = a(35) for all n >= 36. - _Daniel Suteu_, Mar 15 2022
%H Daniel Suteu, <a href="/A351162/b351162.txt">Table of n, a(n) for n = 1..36</a>
%H Daniel Suteu, <a href="/A351162/a351162.pl.txt">Perl program</a>
%e 2048 has 12 divisors. LCM of 2048 and 60 (smallest number with 12 divisors) is 30720.
%t f[n_] := Module[{d = DivisorSigma[0, n], k = 1}, While[DivisorSigma[0, k] != d, k++]; k]; a[1] = 2048; a[n_] := a[n] = LCM[a[n - 1], f[a[n - 1]]]; Array[a, 5] (* _Amiram Eldar_, Feb 04 2022 *)
%Y Cf. A140635.
%K nonn
%O 1,1
%A _J. Lowell_, Feb 04 2022
%E a(5)-a(7) from _Amiram Eldar_, Feb 04 2022
%E a(8)-a(17) from _Jon E. Schoenfield_ and _Daniel Suteu_, Mar 15 2022
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