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Square of LCM of {1, 2, ..., n}.
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%I #21 Oct 27 2023 22:00:44

%S 1,4,36,144,3600,3600,176400,705600,6350400,6350400,768398400,

%T 768398400,129859329600,129859329600,129859329600,519437318400,

%U 150117385017600,150117385017600,54192375991353600,54192375991353600,54192375991353600,54192375991353600

%N Square of LCM of {1, 2, ..., n}.

%C a(n) is the least common multiple (or LCM) of {1, 4, 9, 16, ..., n^2}.

%H T. D. Noe, <a href="/A051418/b051418.txt">Table of n, a(n) for n = 1..200</a>

%H Jon T. Butler, Tsutomu Sasao, <a href="https://doi.org/10.1109/ISMVL.2019.00032">Realizing all Index Generation Functions by the Row-Shift Method</a>, IEEE 49th International Symposium on Multiple-Valued Logic (ISMVL 2019).

%H <a href="/index/Lc#lcm">Index entries for sequences related to lcm's</a>

%F a(n) = A003418(n)^2.

%e a(5) = lcm {1, 4, 9, 16, 25} = 3600.

%t Table[LCM@@Range[n],{n,20}]^2 (* _Harvey P. Dale_, Mar 28 2011 *)

%o (Python) # generator of sequence

%o from math import lcm

%o from itertools import accumulate, count, islice

%o def sqr(x): return x*x

%o def agen(): yield from map(sqr, accumulate(count(1), lcm))

%o print(list(islice(agen(), 22))) # _Michael S. Branicky_, Oct 04 2022

%Y Cf. A003418.

%K easy,nice,nonn

%O 1,2

%A _Asher Auel_