A103520 a(1) = 1, a(n) = product of n successive numbers starting with a(n-1) + 1.

1, 6, 504, 65813284680, 1234718152224069224489356305213161520251951242625962440

Offset: 1

Author

Amarnath Murthy, Feb 10 2005

Keywords

• easy
• nonn

Comments

a(6) has 325 digits and a(7) has 2272 digits. - Harvey P. Dale, Aug 23 2014

Examples

			a(2) = 2*3 = 6, a(3) = 7*8*9 = 504.
		

Crossrefs

Cf. A103519.

Programs

Mathematica

nxt[{n_,a_}]:={n+1,Times@@Range[a+1,a+1+n]}; Transpose[NestList[nxt,{1,1},5]][[2]] (* Harvey P. Dale, Aug 23 2014 *)

Formula

a(n+1) = !{a(n)+n +1}/!{a(n)}

Extensions

More terms from Olaf Voß, Feb 26 2005. (The next term is too large to include.)