A158294 Averages of squares of divisors of numbers in A020486 (i.e., numbers m with property that average of squares of divisors is an integer: sigma_0(m) divides sigma_2(m)).

1, 5, 7, 13, 25, 61, 35, 85, 65, 145, 181, 91, 125, 265, 217, 205, 175, 421, 481, 305, 325, 685, 425, 841, 925, 427, 1105, 341, 817, 725, 595, 1405, 793, 905, 1741, 455, 1861, 1105, 2245, 1015, 1325, 2521, 2665, 1085, 1267, 1525, 3121, 3445, 875, 1885, 2105

Offset: 1

Author

Jaroslav Krizek, Mar 15 2009

Keywords

• nonn

Comments

a(n) = A001157(A020486(n))/A000005(A020486(n)).

Examples

			a(12) = A001157(A020486(12))/A000005(A020486(12)) = A001157(20)/A000005(20) = 546/6 = 91.
		

Links

• Zak Seidov, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000005, A001157, A020486.

Programs

Haskell

a158294 n = (a001157 $ a020486 n) `div` (a000005 $ a020486 n)
-- Reinhard Zumkeller, Jan 15 2013