A109390 Entries in 3-dimensional solid related to Prouhet-Tarry problem.

1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 2, 5, 2, 1, 5, 5, 1, 1, 2, 1, 1, 1, 3, 7, 3, 3, 12, 12, 3, 1, 7, 12, 7, 1, 1, 3, 3, 1, 1, 1, 4, 9, 4, 6, 22, 22, 6, 4, 22, 36, 22, 4, 1, 9, 22, 22, 9, 1, 1, 1, 5, 11, 5, 10, 35, 35, 10, 10, 50, 80, 50, 10, 5, 35, 80, 80, 35, 5, 1, 11, 35, 50

Offset

0,7

Comments

Entries of slices [n,1] in A109672, read by rows.

Slice [n,0] gives A046816, slice [0,k] gives A109649, slice [n,n] gives A109673, slice [1,k] gives A109393.

Links

Table of n, a(n) for n=0..83.

Formula

Sum of terms in 2D slice [n, 1] is 3^(n+1).

Example

Slice [0,1]:
... 1 1 ...
.... 1 ....
Slice [1,1]:
... 1 1 ...
.. 1 3 1 ...
... 1 1 ...
Slice [2,1]:
.... 1 1 ....
... 2 5 2 ...
.. 1 5 5 1 ...
... 1 2 1 ...
Slice [3,1]:
..... 1 1 .....
.... 3 7 3 ....
... 3 12 12 3 ...
.. 1 7 12 7 1 ...
... 1 3 3 1 ...
Slice [4,1]:
...... 1 1 ......
..... 4 9 4 .....
.... 6 22 22 6 ....
... 4 22 36 22 4 ...
.. 1 9 22 22 9 1 ...
... 1 4 6 4 1 ...
Slice [5,1]:
....... 1 1 .......
...... 5 11 5 ......
..... 10 35 35 10 .....
.... 10 50 80 50 10 ....
... 5 35 80 80 35 5 ...
.. 1 11 35 50 35 11 1 ...
... 1 5 10 10 5 1 ...

Crossrefs

Cf. A109393.

Sequence in context: A137578 A200146 A319095 * A130046 A349509 A262619

Adjacent sequences: A109387 A109388 A109389 * A109391 A109392 A109393

Keyword

nonn,tabf,easy

Author

Philippe Deléham, Aug 26 2005

Status

approved