A181105 Triangle T(n,k) read by rows. T(n,k)=abs(A181101)*n/k.

1, 2, 0, 3, 0, 0, 0, 2, 0, 0, 5, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 11, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 13, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0

Offset

1,2

Comments

Let A=T(n,k)*T(n,k), B=A*A, C=B*B, D=C*C, and so on. Then the first column in the last matrix (D) converges to the natural numbers. Rows sums are (unsurprisingly) A020639. Except for the first column, the largest and last element in the columns are also A020639.

Links

Table of n, a(n) for n=1..105.

Example

Triangle starts:
1,
2,0,
3,0,0,
0,2,0,0,
5,0,0,0,0,
0,0,2,0,0,0,
7,0,0,0,0,0,0,
0,0,0,2,0,0,0,0,
0,0,3,0,0,0,0,0,0,
0,0,0,0,2,0,0,0,0,0,
11,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,2,0,0,0,0,0,0,
13,0,0,0,0,0,0,0,0,0,0,0,0,

Crossrefs

Cf. A181101, A020639.

Sequence in context: A255308 A079302 A138806 * A142971 A104117 A114511

Adjacent sequences: A181102 A181103 A181104 * A181106 A181107 A181108

Keyword

nonn,tabl

Author

Mats Granvik, Gary W. Adamson, Oct 03 2010

Status

approved