A060401 a(n) = minimal m such that m>n, n divides m, n-1 divides m-1, n-2 divides m-2 and so on down to 1 divides m-n+1.

2, 4, 9, 16, 65, 66, 427, 848, 2529, 2530, 27731, 27732, 360373, 360374, 360375, 720736, 12252257, 12252258, 232792579, 232792580, 232792581, 232792582, 5354228903, 5354228904, 26771144425, 26771144426, 80313433227, 80313433228, 2329089562829, 2329089562830

Offset: 1

Author

Christopher Burrows (cburrows(AT)math.upenn.edu), Apr 04 2001

Keywords

• nonn

Comments

A099427(a(n)) = n + 1. - Reinhard Zumkeller, Jul 02 2011

Examples

			a(5) = 65 because 5|65, 4|64, 3|63, 2|62, 1|61 and 65 is minimal.
		

Links

• Robert Israel, Table of n, a(n) for n = 1..2296

Crossrefs

Rightmost diagonal of triangle in A075059. Cf. A075061, A075062.

Cf. A003418.

Programs

Maple

seq(n+ilcm($1..n),n=1..100); # Robert Israel, Jul 19 2016

Formula

a(n) = n + lcm(seq(i, i=1..n)).

a(n) = n + A003418(n). - Robert Israel, Jul 19 2016