A244329 a(n) = floor(antisigma(n) / sigma(n)) = floor(A024816(n) / A000203(n)).

0, 0, 0, 0, 1, 0, 2, 1, 2, 2, 4, 1, 5, 3, 4, 3, 7, 3, 8, 4, 6, 6, 10, 4, 9, 7, 8, 6, 13, 5, 14, 7, 10, 10, 12, 6, 17, 11, 12, 8, 19, 8, 20, 10, 12, 14, 22, 8, 20, 12, 17, 13, 25, 11, 20, 12, 19, 18, 28, 9, 29, 19, 18, 15, 24, 14, 32, 17, 24, 16, 34, 12, 35, 23

Offset: 1

Author

Jaroslav Krizek, Jul 08 2014

Keywords

• nonn

Comments

RECORD transform of a(n) is A140475 (union of number 1 and primes >= 5).

Sequence of numbers n such that a(n) = floor(antisigma(n) / n) = A046022.

Sequence of numbers n such that a(n) = a(n+1) = A244666.

Examples

			For n = 10; a(10) = floor(A024816(10) / A000203(10)) = floor(37 / 18) = 2.
		

Links

• Paolo Xausa, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000203, A000217, A024816, A046022, A140475, A244327, A244328, A244666.

Programs

Magma

[Floor(((n*(n+1)div 2)-SumOfDivisors(n)) div (SumOfDivisors(n))) : n in [1..1000]];

Mathematica

A244329[n_] := Floor[(n*(n + 1)/2 - #)/#] & [DivisorSigma[1, n]];
Array[A244329, 100] (* Paolo Xausa, Sep 01 2024 *)

Formula

a(n) = A244327(n) - A244328(n) for n >= 7.