A028283 Central elements in 4-Pascal triangle A028275 (by row).

1, 4, 10, 32, 110, 392, 1428, 5280, 19734, 74360, 281996, 1074944, 4115020, 15808912, 60917800, 235350720, 911315430, 3535767000, 13742347740, 53495534400, 208537056420, 813950932080, 3180614712600, 12441628655040

Offset: 0

Author

Mohammad K. Azarian

Keywords

• nonn
• easy

Comments

Equals A000984, [1, 2, 6, 20, 70, ...] convolved with [1, 2, 0, 0, 0, ...]. - Gary W. Adamson, Jun 05 2009

Crossrefs

Cf. A000108, A028275, A051960.

Formula

a(n) = 2*A051960(n-1).

a(n) = 2*A000108(n)*(3n-1). - Ralf Stephan, Aug 24 2003