A179806 Irregular triangle by rows, M*Q. M = triangle with (1,2,3,...) in every column, with the leftmost column shifted upwards one row. Q = a diagonalized variant of odd-indexed Fibonacci numbers.
1, 2, 3, 2, 4, 4, 5, 5, 6, 10, 13, 6, 8, 15, 26, 34, 7, 10, 20, 39, 68, 89, 8, 12, 25, 52, 102, 178, 233, 9, 14, 30, 65, 136, 267, 466, 610, 10, 16, 35, 78, 170, 356, 699, 1220, 1597
Offset: 1
Examples
First few rows of the triangle: 1; 2; 3, 2; 4, 4, 5; 5, 6, 10, 13; 6, 8, 15, 26, 34; 7, 10, 20, 39, 68, 89; 8, 12, 25, 52, 102, 178, 233; 9, 14, 30, 65, 136, 267, 466, 610; 10, 16, 35, 78, 170, 356, 699, 1220, 1597; 11, 18, 40, 91, 204, 445, 932, 1830, 3194, 4181; 12, 20, 45, 104, 238, 534, 1165, 2440, 4791, 8362, 10946; ...
Crossrefs
Cf. A001519.
Formula
Triangle, M*Q; where M = a triangle with (1,2,3,...) in every column with the leftmost column shifted upwards one row. Q = an infinite matrix with the odd-indexed Fibonacci numbers as the right border: (1, 2, 5, 13,...) and
the rest zeros.
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