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%I #14 Nov 03 2020 03:17:16
%S 0,2,3,12,23,61,135,306,679,1499,3257,7053,15167,32443,69080,146533,
%T 309743,652762,1371897,2876284,6017100,12562511,26180328,54469099,
%U 113151406,234723068,486276265,1006195365,2079647131,4293758081,8856361762,18250277543
%N Number of compositions of 2n where the difference between largest and smallest parts equals n.
%H Alois P. Heinz, <a href="/A323111/b323111.txt">Table of n, a(n) for n = 1..200</a>
%F a(n) = A214258(2n,n).
%F Conjecture: a(n) ~ n * 2^(n-3). - _Vaclav Kotesovec_, Jan 07 2019
%e a(2) = 2: 13, 31.
%e a(3) = 3: 114, 141, 411.
%e a(4) = 12: 1115, 1151, 1511, 5111, 125, 152, 215, 251, 512, 521, 26, 62.
%e a(5) = 23: 11116, 11161, 11611, 16111, 61111, 1126, 1162, 1216, 1261, 1612, 1621, 2116, 2161, 2611, 6112, 6121, 6211, 136, 163, 316, 361, 613, 631.
%Y Cf. A117989 (the same for partitions), A214258.
%K nonn
%O 1,2
%A _Alois P. Heinz_, Jan 04 2019
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