A160644 First of two sequences bisecting the second differences of the partition numbers (see A053445).

1, 1, 2, 3, 4, 7, 10, 14, 22, 32, 45, 67, 95, 134, 192, 269, 373, 521, 718, 983, 1346, 1827, 2465, 3323, 4449, 5929, 7882, 10426, 13735, 18047, 23613, 30788, 40034, 51877, 67013, 86341, 110905, 142063, 181529, 231340, 294077, 372977, 471908, 595725, 750432

Offset: 1

Author

Alford Arnold, May 21 2009

Keywords

• easy
• nonn

Comments

A160644 also counts selected unrestricted partition having an EVEN total and with minimum part two. For example it counts these three partitions of eight: 4+4, 3+3+2, and 2+2+2+2.

Examples

			A053445 begins
1 0 1 0 2 0 3 1 4 2 7 3 10 7 14 11 22 17 32 28 45 ...
therefore a(n) begins
1 1 2 3 4 7 10 14 22 32 45 67 95 134 192 ...
		

Links

• Nathaniel Johnston, Table of n, a(n) for n = 1..2500

Crossrefs

Cf. A000041, A002685, A053445, A160643, A161921 (the other bisection).

Programs

Mathematica

Take[Differences[PartitionsP[Range[0,100]],2],{1,-1,2}] (* Harvey P. Dale, Aug 05 2019 *)