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 A078713 Sum of squares of the distances between successive divisors of n. 2

%I

%S 0,1,4,5,16,11,36,21,40,35,100,43,144,75,108,85,256,101,324,131,216,

%T 203,484,171,416,291,364,259,784,273,900,341,552,515,804,385,1296,651,

%U 780,519,1600,551,1764,659,960,971,2116,683,1800,885,1356,931,2704,911,1988

%N Sum of squares of the distances between successive divisors of n.

%H Harvey P. Dale, <a href="/A078713/b078713.txt">Table of n, a(n) for n = 1..1000</a>

%e The divisors of 10 are 1, 2, 5, 10 and the sum of the squares of the distances between successive divisors = (2-1)^2 + (5-2)^2 + (10-5)^2 = 35. Hence a(10) = 35.

%t f[n_] := Module[{d, l, s, i}, d = Divisors[n]; l = Length[d]; s = 0; For[i = 1, i < l, i++, s = s + (d[[i + 1]] - d[[i]])^2]; s]; Table[f[n], {n, 1, 100}]

%t Table[Total[Differences[Divisors[n]]^2],{n,60}] (* _Harvey P. Dale_, Apr 10 2018 *)

%K nonn

%O 1,3

%A _Joseph L. Pe_, Dec 19 2002

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Last modified November 20 23:03 EST 2018. Contains 317427 sequences. (Running on oeis4.)