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Maximal GCD of four positive integers with sum n.
8

%I #24 Sep 21 2022 11:27:45

%S 1,1,1,1,2,1,2,1,3,1,2,3,4,1,3,1,5,3,2,1,6,5,2,3,7,1,6,1,8,3,2,7,9,1,

%T 2,3,10,1,7,1,11,9,2,1,12,7,10,3,13,1,9,11,14,3,2,1,15,1,2,9,16,13,11,

%U 1,17,3,14,1,18,1,2,15,19,11,13,1,20,9,2,1,21,17,2,3,22,1,18,13,23,3,2,19,24,1,14,11,25

%N Maximal GCD of four positive integers with sum n.

%t a[n_] := GCD @@@ IntegerPartitions[n, {4}] // Max;

%t Table[a[n], {n, 4, 100}] (* _Jean-François Alcover_, Sep 21 2022 *)

%Y Cf. A008233, A129649.

%Y Maximal GCD of k positive integers with sum n for k = 2..10: A032742 (k=2,n>=2), A355249 (k=3), this sequence (k=4), A355366 (k=5), A355368 (k=6), A355402 (k=7), A354598 (k=8), A354599 (k=9), A354601 (k=10).

%K nonn

%O 4,5

%A _Wesley Ivan Hurt_, Jun 29 2022