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Maximum LCM of partitions of n into pairwise coprime parts that are >= 2.
1

%I #17 Jan 04 2021 13:56:24

%S 2,3,4,6,6,12,15,20,30,30,60,42,84,105,140,210,210,420,280,330,360,

%T 840,504,1260,1155,1540,2310,2520,4620,3080,5460,3960,9240,5544,13860,

%U 6930,16380,15015,27720,30030,32760,60060,40040,45045,51480,120120,72072,180180

%N Maximum LCM of partitions of n into pairwise coprime parts that are >= 2.

%C a(n) <= A123131(n).

%H Fausto A. C. Cariboni, <a href="/A340267/b340267.txt">Table of n, a(n) for n = 2..260</a>

%e For n=22 we have a(22) = 360 since 22 = 5 + 8 + 9 and lcm([5, 8, 9]) = 360.

%e Note a(22) = 360 < A123131(22) = 420.

%o (PARI) isok(p) = {for (i=1, #p, for (j=i+1, #p, if (gcd(p[i], p[j]) > 1, return(0)););); return(1);}

%o a(n) = {my(x=1); forpart(p=n, if ((vecmin(p)>=2) && isok(p), x = max(x, lcm(Vec(p))));); x;} \\ _Michel Marcus_, Jan 03 2021

%Y Cf. A007359, A007360, A123131.

%K nonn

%O 2,1

%A _Fausto A. C. Cariboni_, Jan 02 2021