A169827 Multiples of 840.

0, 840, 1680, 2520, 3360, 4200, 5040, 5880, 6720, 7560, 8400, 9240, 10080, 10920, 11760, 12600, 13440, 14280, 15120, 15960, 16800, 17640, 18480, 19320, 20160, 21000, 21840, 22680, 23520, 24360, 25200, 26040, 26880, 27720, 28560, 29400, 30240, 31080, 31920

Offset: 0

Author

N. J. A. Sloane, May 30 2010

Keywords

• nonn
• easy

Comments

Numbers that are divisible by all of 1,2,3,4,5,6,7,8.

Links

• Erich Friedman, What's Special About This Number?
• Index entries for linear recurrences with constant coefficients, signature (2,-1).

Crossrefs

Cf. A001477, A005843, A008596, A008603, A135628, A169823, A169825.

Cf. A249674, A317095.

Programs

Mathematica

840*Range[0,40] (* Harvey P. Dale, Nov 03 2015 *)

PARI

a(n)=840*n \\ Charles R Greathouse IV, Apr 16 2024

Formula

From Elmo R. Oliveira, Apr 16 2024: (Start)

G.f.: 840*x/(x-1)^2.

E.g.f.: 840*x*exp(x).

a(n) = 840*n = 2*a(n-1) - a(n-2) for n >= 2.

a(n) = 2*A169825(n) = 14*A169823(n) = 21*A317095(n) = 28*A249674(n) = 30*A135628(n) = 40*A008603(n) = 60*A008596(n) = 420*A005843(n) = 840*A001477(n). (End)