A169946 Triangle read by rows: A169945 with rows reversed.

1, 1, 1, 2, 1, 1, 3, 3, 1, 1, 2, 8, 4, 1, 1, 3, 6, 16, 5, 1, 1, 2, 11, 14, 29, 6, 1, 1, 3, 9, 29, 29, 49, 7, 1, 1, 2, 14, 22, 74, 52, 82, 8, 1, 1, 3, 12, 42, 58, 160, 96, 130, 9, 1, 1, 2, 17, 30, 126, 128, 344, 160, 205, 10, 1, 1, 3, 15, 53, 98, 314, 294, 676, 277, 305, 11

Offset

0,4

Comments

The heuristic formula for the third column (verified for 2<=n<=21) is 3*n/2+7*(1-(-1)^n)/4. [From R. J. Mathar, Aug 02 2010]

Links

Table of n, a(n) for n=0..75.

Index entries for sequences related to carryless arithmetic

Formula

Wanted: a recurrence. Are any of A169940-A169954 related to any other entries in the OEIS?

Example

Triangle begins:
[1, 1]
[1, 2, 1]
[1, 3, 3, 1]
[1, 2, 8, 4, 1]
[1, 3, 6, 16, 5, 1]
[1, 2, 11, 14, 29, 6, 1]
[1, 3, 9, 29, 29, 49, 7, 1]
[1, 2, 14, 22, 74, 52, 82, 8, 1]
[1, 3, 12, 42, 58, 160, 96, 130, 9, 1]
[1, 2, 17, 30, 126, 128, 344, 160, 205, 10, 1]
[1, 3, 15, 53, 98, 314, 294, 676, 277, 305, 11, 1]
[1, 2, 20, 38, 185, 232, 796, 576, 1333, 450, 450, 12, 1]
[1, 3, 18, 64, 147, 501, 628, 1796, 1177, 2477, 712, 654, 13, 1]
[1, 2, 23, 46, 251, 368, 1425, 1370, 4075, 2212, 4563, 1086, 947, 14, 1]
[1, 3, 21, 75, 205, 729, 1117, 3515, 3265, 8535, 4289, 7997, 1657, 1343, 15, 1]
...

Crossrefs

Related to thickness: A169940-A169954, A061909.

Sequence in context: A080381 A080396 A155582 * A160832 A351522 A157458

Adjacent sequences: A169943 A169944 A169945 * A169947 A169948 A169949

Keyword

nonn,tabf

Author

N. J. A. Sloane, Aug 01 2010

Status

approved