A171999 Triangle of trinomial coefficients.

1, 1, 2, 1, 3, 6, 1, 4, 6, 12, 1, 5, 10, 20, 30, 1, 6, 15, 20, 30, 60, 90, 1, 7, 21, 35, 42, 105, 140, 210, 1, 8, 28, 56, 70, 168, 280, 420, 560, 1, 9, 36, 72, 84, 126, 252, 504, 630, 756, 1260, 1680, 1, 10, 45, 90, 120, 210, 252, 360, 840, 1260, 2520, 3150, 4200, 1, 11, 55

Offset: 1

Author

Clark Kimberling, Jan 21 2010

Keywords

• nonn
• tabf

Comments

Number of numbers in row n is given by A086753.

Row sums: A092255.

See A046816, Pascal's pyramid of trinomial coefficients.

Examples

			First six rows:
1
1...2
1...3...6
1...4...6....12
1...5...10...20...30
1...6...15...20...30...60...90
		

Crossrefs

Cf. A036038, A046816, A092255.