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A027129
a(n) = T(n,n) + T(n,n+1) + ... + T(n,2n), T given by A027113.
1
1, 3, 9, 27, 79, 231, 672, 1951, 5662, 16439, 47776, 139025, 405110, 1182107, 3454035, 10105373, 29600389, 86800887, 254797772, 748646741, 2201587214, 6479524339, 19084115993, 56246912653, 165882843095, 489509315203
OFFSET
0,2
CROSSREFS
Sequence in context: A238440 A269578 A026289 * A077844 A077827 A299108
KEYWORD
nonn
STATUS
approved