

A108286


Triangle read by rows; columns are simple recursive sequences.


2



1, 3, 1, 6, 4, 1, 10, 11, 5, 1, 15, 26, 18, 6, 1, 21, 57, 58, 27, 7, 1, 28, 120, 179, 112, 38, 8, 1, 36, 247, 543, 453, 194, 51, 9, 1, 45, 502, 1636, 1818, 975, 310, 66, 10, 1
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OFFSET

1,2


COMMENTS

Left column = triangular numbers; Col. 2, (1, 4, 11...) = A000295; Col. 3, (1, 5, 18...) = A000340; Col. 4, (1, 6, 27...) = A014825; Col.5, (1, 7, 38...) = A014827.


LINKS

Table of n, a(n) for n=1..45.


FORMULA

rth term in nth column: initial "1", then a(r) = n*a(r1) + r. Diagonals of A108285 become the columns of A108286.


EXAMPLE

First few rows of the triangle are:
1;
3, 1;
6, 4, 1;
10, 11; 5, 1;
15, 26, 18, 6, 1;
21, 57, 58, 27, 7, 1;
...
3rd offset column: (1, 5, 18, 58...) = "1", then a(r) = 3*a(r1) + r; e.g. 58 = 3*18 + 4 since 58 is the fourth term in the third column.


CROSSREFS

Cf. A108285, A000295, A000340, A014825, A014827.
Sequence in context: A104712 A122177 A255874 * A185944 A131415 A210230
Adjacent sequences: A108283 A108284 A108285 * A108287 A108288 A108289


KEYWORD

nonn,tabl


AUTHOR

Gary W. Adamson, May 31 2005


STATUS

approved



