A143309 Triangle read by rows, A054525 * A143308, 1<=k<=n.

1, 3, 2, 5, 3, 3, 8, 6, 4, 4, 9, 5, 5, 5, 5, 15, 13, 9, 6, 6, 6, 13, 7, 7, 7, 7, 7, 7, 20, 16, 12, 12, 8, 8, 8, 8, 21, 15, 15, 9, 9, 9, 9, 9, 9, 27, 23, 15, 15, 15, 10, 10, 10, 10, 10, 21, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 40, 36, 32, 26, 18, 18, 12, 12, 12, 12, 12, 12, 25, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13

Offset

1,2

Comments

Row sums = A069097: (1, 5, 11, 22, 29, 55,...).

Left border = A018804: (1, 3, 5, 8, 9, 15,...).

Links

Table of n, a(n) for n=1..91.

Formula

Mobius transform of triangle A143308.

Example

First few rows of the triangle =
1;
3, 2;
5, 3, 3;
8, 6, 4, 4;
9, 5, 5, 5, 5;
15, 13, 9, 6, 6, 6;
13, 7, 7, 7, 7, 7, 7;
...

Crossrefs

Cf. A018804, A069097, A143308.

Sequence in context: A194736 A333363 A130299 * A206562 A155981 A057958

Adjacent sequences: A143306 A143307 A143308 * A143310 A143311 A143312

Keyword

nonn,tabl

Author

Gary W. Adamson, Aug 06 2008

Extensions

a(56) = 10 removed and more terms from Georg Fischer, Jul 13 2023

Status

approved