A056225 - OEIS

%I #10 Dec 10 2017 05:02:46

%S 1,-2,3,3,-7,-3,16,3,-27,-27,51,-131,-198,153,680,87,-144,1728,837,

%T -612,-1209,8323,7692,-18603,19731,90355,53811,-11862,-26325,-4617,

%U 43011,-146043,-285804,4338927,-10634576,-9106743,-4841163,25073595,-39991893,-78120734,-38434140,71394066,-79624323,103828878

%N Hankel transform of number of divisors sequence (A000005).

%H Robert Israel, <a href="/A056225/b056225.txt">Table of n, a(n) for n = 1..1000</a>

%p f:= (i,j) -> numtheory:-tau(i+j-1): A056225:= n -> LinearAlgebra:-Determinant(Matrix(n,n,f)):

%p map(A056225,[$1..100]); # _Robert Israel_, Dec 08 2017

%t f[n_] := Det@Table[DivisorSigma[0, (i + j - 1)], {i, n}, {j, n}]; Array[f, 44] (* _Robert G. Wilson v_, Dec 08 2017 *)

%Y See A001906 for definition of Hankel transform.

%K sign,easy

%O 1,2

%A _N. J. A. Sloane_, Aug 06 2000

%E More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 05 2003

%E More terms from _Robert Israel_, Dec 08 2017