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Sum of all odd-indexed parts minus the sum of all even-indexed parts of all partitions of n, with the parts written in nondecreasing order.
7

%I #21 May 23 2012 09:38:49

%S 1,2,3,4,5,8,9,14,18,26,32,48,57,82,102,138,169,230,278,370,450,584,

%T 709,914,1102,1400,1692,2124,2555,3186,3818,4720,5649,6926,8269,10078,

%U 11989,14526,17249,20782,24603,29508,34843,41600,49008,58258,68468,81098

%N Sum of all odd-indexed parts minus the sum of all even-indexed parts of all partitions of n, with the parts written in nondecreasing order.

%C It appears that A066897 is also another version of this sequence but with the parts written in nonincreasing order.

%H Alois P. Heinz, <a href="/A194714/b194714.txt">Table of n, a(n) for n = 1..1000</a>

%e a(6) = 37 - 29 = 8 because the partitions of 6 written in nondecreasing order are

%e .

%e . 6 = 6

%e . 3 - 3 = 0

%e . 2 - 4 = -2

%e . 2 - 2 + 2 = 2

%e . 1 - 5 = -4

%e . 1 - 2 + 3 = 2

%e . 1 - 1 + 4 = 4

%e . 1 - 1 + 2 - 2 = 0

%e . 1 - 1 + 1 - 3 = -2

%e . 1 - 1 + 1 - 1 + 2 = 2

%e . 1 - 1 + 1 - 1 + 1 - 1 = 0

%e ----------------------------------

%e . 20 - 21 + 14 - 7 + 3 - 1 = 8

%Y Cf. A066897, A135010, A138121, A141285, A194853.

%K nonn

%O 1,2

%A _Omar E. Pol_, Feb 12 2012

%E More terms from _Alois P. Heinz_, Feb 12 2012