A257943 Array A read by upward antidiagonals in which the entry in row n and column k is defined by A(n,k) = (1 + 3^(n-1)*(2*k - 1))/2, n,k >= 1.

1, 2, 2, 5, 5, 3, 14, 14, 8, 4, 41, 41, 23, 11, 5, 122, 122, 68, 32, 14, 6, 365, 365, 203, 95, 41, 17, 7, 1094, 1094, 608, 284, 122, 50, 20, 8, 3281, 3281, 1823, 851, 365, 149, 59, 23, 9, 9842, 9842, 5468, 2552, 1094, 446, 176, 68, 26, 10

Offset

1,2

Links

Table of n, a(n) for n=1..55.

Example

Array A begins:
.     1      2      3      4      5       6       7       8       9      10
.     2      5      8     11     14      17      20      23      26      29
.     5     14     23     32     41      50      59      68      77      86
.    14     41     68     95    122     149     176     203     230     257
.    41    122    203    284    365     446     527     608     689     770
.   122    365    608    851   1094    1337    1580    1823    2066    2309
.   365   1094   1823   2552   3281    4010    4739    5468    6197    6926
.  1094   3281   5468   7655   9842   12029   14216   16403   18590   20777
.  3281   9842  16403  22964  29525   36086   42647   49208   55769   62330
.  9842  29525  49208  68891  88574  108257  127940  147623  167306  186989

Mathematica

(* Array: *)
Grid[Table[(1 + 3^(n - 1)*(2*k - 1))/2, {n, 10}, {k, 10}]]
(* Array antidiagonals flattened: *)
Flatten[Table[(1 + 3^(n - k)*(2*k - 1))/2, {n, 10}, {k, n}]]

Crossrefs

Cf. A191450, A254051.

Sequence in context: A161622 A116559 A210802 * A008280 A239005 A236935

Adjacent sequences: A257940 A257941 A257942 * A257944 A257945 A257946

Keyword

nonn,tabl

Author

L. Edson Jeffery, May 13 2015

Status

approved