cp's OEIS Frontend

A275065 Number of permutations p of [n] such that p(i)-i is a multiple of ten for all i in [n].

%I A275065 #11 Oct 02 2018 04:59:37
%S A275065 1,1,1,1,1,1,1,1,1,1,1,2,4,8,16,32,64,128,256,512,1024,3072,9216,
%T A275065 27648,82944,248832,746496,2239488,6718464,20155392,60466176,
%U A275065 241864704,967458816,3869835264,15479341056,61917364224,247669456896,990677827584,3962711310336
%N A275065 Number of permutations p of [n] such that p(i)-i is a multiple of ten for all i in [n].
%H A275065 Alois P. Heinz, <a href="/A275065/b275065.txt">Table of n, a(n) for n = 0..699</a>
%F A275065 a(n) = Product_{i=0..9} floor((n+i)/10)!.
%F A275065 a(n) = ((m+1)!)^10/(m+1)^(10-k) where m=floor(n/10)=A059995(n) and k=n mod 10 =A010879(n). - _Robert Israel_, Jul 26 2016
%F A275065 a(n) ~ (2*Pi*n)^(9/2) * n! / 10^(n + 5). - _Vaclav Kotesovec_, Oct 02 2018
%p A275065 f:= n -> mul(floor((n+i)/10)!,i=0..9):
%p A275065 map(f, [$0..30]); # _Robert Israel_, Jul 26 2016
%t A275065 Table[Product[Floor[(n + i)/10]!, {i, 0, 9}], {n, 0, 40}] (* _Vaclav Kotesovec_, Oct 02 2018 *)
%Y A275065 Column k=10 of A275062.
%Y A275065 Cf. A010879, A059995.
%K A275065 nonn
%O A275065 0,12
%A A275065 _Alois P. Heinz_, Jul 15 2016