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A368242
Numbers k whose number of proper divisors is greater than sqrt(k).
0
6, 8, 12, 18, 20, 24, 30, 36, 40, 42, 48, 60, 72, 80, 84, 90, 96, 108, 120, 144, 168, 180, 210, 216, 240, 252, 288, 336, 360, 420, 480, 504, 720, 840
OFFSET
1,1
FORMULA
12 is a term since it has 5 proper divisors (1,2,3,4,6), and 5 > sqrt(12).
MATHEMATICA
Select[Range[1, 10000000], Length[Divisors[#]] - 1 > Sqrt[#] &]
PROG
(PARI) for(k=1, 10^6, if(numdiv(k)-1 > sqrtint(k), print1(k, ", "))) \\ Joerg Arndt, Jan 06 2024
CROSSREFS
KEYWORD
nonn,fini,full
AUTHOR
Zdenek Cervenka, Dec 18 2023
STATUS
approved