A089141 Square array, read by antidiagonal: T(n,k) = n*T(n,k-1)+(-1)^k*T(n,floor(k/2)).

1, 2, 1, 1, 3, 1, 3, 5, 4, 1, 1, 13, 11, 5, 1, 2, 23, 37, 19, 6, 1, 1, 51, 107, 81, 29, 7, 1, 4, 97, 332, 319, 151, 41, 8, 1, 1, 207, 985, 1295, 749, 253, 55, 9, 1, 2, 401, 2992, 5161, 3774, 1511, 393, 71, 10, 1, 1, 825, 8939, 20725, 19021, 9107, 2743, 577, 89, 11, 1

Offset

1,2

Links

Table of n, a(n) for n=1..66.

Example

Row 1 :1, 2, 1, 3, 1, 2, 1, 2, 1, 4, 1, 2, 1, ...(A001511).
Row 2 :1, 3, 5, 13, 23, 51, 97, 207, 401, 825, 1627, ...(A089067).
Row 3 :1, 4, 11, 37, 107, 332, 985, 2992, 8939, 26924, 80665, ...
Row 4 :1, 5, 19, 81, 319, 1295, 5161,20725, 82819, 331595, 1326061, ...
Row 5 :1, 6, 29, 151, 749, 3774, 19021, 94954, 475519, 2376846, 11888004, ...

Crossrefs

Cf. A001511, A089067.

Sequence in context: A102426 A052920 A320250 * A336084 A375128 A245717

Adjacent sequences: A089138 A089139 A089140 * A089142 A089143 A089144

Keyword

easy,nonn,tabl

Author

Philippe Deléham, Dec 05 2003

Status

approved