A182992 Number of parts of the n-th subshell of the head of the last section of the set of partitions of any even integer >= 2n.

1, 2, 5, 9, 17, 34, 55, 96, 163, 260, 413, 658, 1000, 1528, 2304, 3405, 5003, 7302, 10497, 15022, 21330, 30010, 41980, 58395, 80607, 110740, 151334, 205623, 278119, 374513, 501842, 669828, 890461, 1178960, 1555314

Offset

1,2

Comments

The last section of the set of partitions of 2n contains n subshells.

Also first differences of A182734. - Omar E. Pol, Mar 03 2011

Links

Table of n, a(n) for n=1..35.

Formula

a(1) = 1. a(n) = A138135(2n) - A138135(2n-2), n >= 2.

Example

a(5)=17 because the 5th subshell of the head of the last section of any even integer >= 10 looks like this:
(10 . . . . . . . . . )
( 5 . . . . 5 . . . . )
( 6 . . . . . 4 . . . )
( 7 . . . . . . 3 . . )
( 4 . . . 3 . . 3 . . )
.                (2 . )
.                (2 . )
.                (2 . )
.                (2 . )
.                (2 . )
.                (2 . )
.                (2 . )
The subshell has 17 parts, so a(5)=17.

Crossrefs

Cf. A135010, A138135, A182734, A182742, A182982, A182993, A182994.

Sequence in context: A000569 A292168 A322304 * A115851 A163734 A336141

Adjacent sequences: A182989 A182990 A182991 * A182993 A182994 A182995

Keyword

nonn

Author

Omar E. Pol, Feb 06 2011

Extensions

More terms from Omar E. Pol, Mar 03 2011

Status

approved