A182844 a(0)=0: a(n)=A002865(2*n)+A002865(2*n+1), n>=1.

0, 2, 4, 8, 15, 26, 45, 75, 121, 193, 302, 463, 703, 1052, 1555, 2277, 3301, 4740, 6754, 9548, 13398, 18678, 25873, 35620, 48771, 66418, 89988, 121345, 162878, 217666, 289685, 383994, 507059, 667131, 874656, 1142860, 1488484, 1932575, 2501599, 3228787

Offset

0,2

Comments

a(n) is also the length of the n-th "large mirror" of the "mirror" version of the shell model of partitions A135010.

Links

Nathaniel Johnston, Table of n, a(n) for n = 0..1000

Example

a(0)=0 by definition. a(1)=1+1=2: a(2)=2+2=4. a(3)=4+4=8. a(4)=7+8=15. a(5)=12+14=26. a(6)=21+24=45.

Crossrefs

Cf. A002865, A135010. For another version see A182845.

Sequence in context: A222147 A003241 A279320 * A191630 A125513 A054174

Adjacent sequences: A182841 A182842 A182843 * A182845 A182846 A182847

Keyword

nonn,easy

Author

Omar E. Pol, Jan 24 2011

Extensions

Extended by Nathaniel Johnston, May 06 2011

Status

approved