A123558 Multiplicative encoding of the (1,2)-Pascal triangle (or Lucas triangle) A029635.

2, 18, 1350, 24806250, 94588417300781250, 117849324069921797604001373181152343750, 527608657124852026883960737403192593816085584608183988660956158325750160217285156250

Offset: 1

Author

Jonathan Vos Post, Nov 04 2006

Keywords

• easy
• nonn

Comments

This is to A029635 the (1,2)-Pascal triangle (or Lucas triangle) read by rows" as A007188 "Multiplicative encoding of Pascal triangle: Product p(i+1)^C(n,i)" is to A007318 "Pascal's triangle read by rows."

Examples

			a(1) = 2^1 = 2.
a(2) = 2^1 * 3^2 = 18.
a(3) = 2^1 * 3^3 * 5^2 = 1350.
a(4) = 2^1 * 3^4 * 5^5 * 7^2 = 24806250.
a(5) = 2^1 * 3^5 * 5^9 * 7^7 * 11^2 = 94588417300781250.
a(6) = 2^1 * 3^6 * 5^14 * 7^16 * 11^9 * 13^2 = 117849324069921797604001373181152343750.
		

Crossrefs

Cf. A000040, A007188, A007318, A009766, A029635.

Formula

a(n) = Product_{i=0..n} prime(i+1)^T(n,i), where T(n,i) are the (1,2)-Pascal triangle (or Lucas triangle) as in A029635.