A355366 Maximal GCD of five positive integers with sum n.

1, 1, 1, 1, 1, 2, 1, 2, 1, 2, 3, 2, 1, 3, 1, 4, 3, 2, 1, 4, 5, 2, 3, 4, 1, 6, 1, 4, 3, 2, 7, 6, 1, 2, 3, 8, 1, 7, 1, 4, 9, 2, 1, 8, 7, 10, 3, 4, 1, 9, 11, 8, 3, 2, 1, 12, 1, 2, 9, 8, 13, 11, 1, 4, 3, 14, 1, 12, 1, 2, 15, 4, 11, 13, 1, 16, 9, 2, 1, 14, 17, 2, 3, 11, 1

Offset: 5

Author

Wesley Ivan Hurt, Jun 29 2022

Keywords

• nonn

Crossrefs

Cf. A008382, A129650.

Maximal GCD of k positive integers with sum n for k = 2..10: A032742 (k=2,n>=2), A355249 (k=3), A355319 (k=4), this sequence (k=5), A355368 (k=6), A355402 (k=7), A354598 (k=8), A354599 (k=9), A354601 (k=10).

Programs

Mathematica

a[n_] := GCD @@@ IntegerPartitions[n, {5}] // Max;
Table[a[n], {n, 5, 100}] (* Jean-François Alcover, Sep 21 2022 *)

PARI

a(n) = { my (v=0); forpart(p=n, v=max(v,gcd(Vec(p))),, [5,5]); v } \\ Rémy Sigrist, Jul 01 2022