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Number of partitions of n into positive quarter-squares (cf. A002620).
4

%I #8 Jul 13 2013 12:04:17

%S 1,1,2,2,4,4,7,7,11,12,17,18,26,28,37,40,53,57,74,79,101,109,136,145,

%T 181,195,237,255,308,332,397,427,506,546,641,688,807,868,1007,1081,

%U 1250,1342,1544,1655,1893,2033,2313,2477,2812,3015,3403,3644,4102,4390

%N Number of partitions of n into positive quarter-squares (cf. A002620).

%H Reinhard Zumkeller, <a href="/A197122/b197122.txt">Table of n, a(n) for n = 0..100</a>

%e a(10) = #{9+1, 6+4, 6+2+2, 6+2+1+1, 6+1+1+1+1, 4+4+2, 4+4+1+1, 4+2+2+2, 4+2+2+1+1, 4+2+1+1+1+1, 4+6x1, 2+2+2+2+2, 2+2+2+2+1+1, 2+2+2+1+1+1+1, 2+2+6x1, 2+8x1, 10x1} = 17.

%o (Haskell)

%o a197122 = p (drop 2 a002620_list) where

%o p _ 0 = 1

%o p ks'@(k:ks) m | m < k = 0

%o | otherwise = p ks' (m - k) + p ks m

%Y Cf. A197081, A002378, A000290, A000041.

%K nonn

%O 0,3

%A _Reinhard Zumkeller_, Oct 10 2011