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A143061
Triangle read by rows, A000012 * A127647 * A000012.
4
1, 1, 2, 2, 3, 4, 3, 5, 6, 7, 5, 8, 10, 11, 12, 8, 13, 16, 18, 19, 20, 13, 21, 26, 29, 31, 32, 33, 21, 34, 42, 47, 50, 52, 53, 54, 34, 55, 68, 76, 81, 84, 86, 87, 88, 55, 89, 110, 123, 131, 136, 139, 141, 142, 143, 89, 144, 178, 199, 212, 220, 225, 228, 230, 231
OFFSET
1,3
COMMENTS
Row sums = A014286 (1, 3, 9, 21, 46, 94, ...); left border = Fibonacci numbers.
LINKS
Robert Israel, Table of n, a(n) for n = 1..10011 (rows 1 to 141, flattened)
FORMULA
From Robert Israel, Nov 06 2016: (Start)
T(n,k) = A000045(n+2) - A000045(n+2-k) for 1 <= k <= n.
G.f. as triangle: x*y*(1+x^2*y)/((1-x*y)*(1-x-x^2)*(1-x*y-x^2*y^2)). (End)
EXAMPLE
First few rows of the triangle are:
1;
1, 2;
2, 3, 4;
3, 5, 6, 7;
5, 8, 10, 11, 12;
8, 13, 16, 18, 19, 20;
...
MAPLE
seq(seq(combinat:-fibonacci(i+2)-combinat:-fibonacci(i+2-j), j=1..i), i=1..20); # Robert Israel, Nov 06 2016
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Jul 20 2008
EXTENSIONS
Corrected by Dintle N Kagiso, Nov 06 2016
STATUS
approved