A357687 Nonsquarefree numbers k such that A048250(k) > 2*k.

401120980260, 14841476269620, 16445960190660, 17248202151180, 18852686072220, 608500527054420, 638183479593660, 697549384672140, 707176288198380, 772960128961020, 810665501105460, 26165522663340060, 28599524771557740, 29994623540902020, 33237285545323860, 1229779565176982820

Offset

1,1

Comments

The squarefree numbers k such that A048250(k) > 2*k are the squarefree abundant numbers (A087248).

The least odd term is 3*prime(553)#/2 = 3.735...*10^1709.

Links

Table of n, a(n) for n=1..16.

Mathematica

q[n_] := Module[{f = FactorInteger[n]}, AnyTrue[f[[;; , 2]], # > 1 &] && Times @@ (f[[;; , 1]]+1) > 2*n];

Prog

(PARI) is(n) = {my(f = factor(n)); if(n == 1 || vecmax(f[, 2]) == 1, return(0)); prod(i=1, #f~, f[i, 1]+1) > 2*n};

Crossrefs

Subsequence of A005101 and A013929.

Cf. A005117, A048250, A087248, A357685, A357686.

Sequence in context: A080122 A269417 A281963 * A363799 A082411 A113952

Adjacent sequences: A357684 A357685 A357686 * A357688 A357689 A357690

Keyword

nonn

Author

Amiram Eldar, Oct 09 2022

Status

approved