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A245560
Row sums of triangle in A144480.
1
1, 2, 6, 14, 36, 82, 196, 436, 1000, 2186, 4884, 10540, 23128, 49428, 107048, 227048, 486864, 1026394, 2183860, 4581244, 9686776, 20237372, 42571896, 88632664, 185653936, 385380932, 804316296, 1665340856, 3464899440, 7158117736, 14853106384
OFFSET
0,2
FORMULA
From N. J. A. Sloane, Aug 07 2014: if n is even, a(n) = (n+2)*2^(n-1)-(n/2)*binomial(n,n/2) otherwise a(n) = (n+2)*2^(n-1)-((n+1)/4)*binomial(n+1,(n+1)/2). This follows easily from the definition.
MAPLE
f:=n->if (n mod 2) = 0 then (n+2)*2^(n-1)-(n/2)*binomial(n, n/2)
else (n+2)*2^(n-1)-((n+1)/4)*binomial(n+1, (n+1)/2); fi;
[seq(f(n), n=0..40)];
CROSSREFS
Cf. A144480.
Sequence in context: A362780 A323027 A110152 * A175654 A017922 A077937
KEYWORD
nonn,easy
AUTHOR
Roger L. Bagula, Oct 11 2008
EXTENSIONS
Edited with more terms by N. J. A. Sloane, Aug 07 2014
STATUS
approved