A034884 -id:A034884 - cp's OEIS frontend

2, 2, 6, 12, 12, 24, 60, 180, 360, 1260, 5040, 15120, 55440, 166320, 831600, 4324320, 36756720, 367567200, 2327925600, 27935107200

Offset: 11

T. D. Noe, May 15 2013

Each of these numbers is the product of small primes. For example, a(30) = 2^7 2^3 5^2 7 11 13 17 19. - T. D. Noe, May 16 2013

Cf. A034884 (n < d(n)^2), A056757 (n < d(n)^3), A225729-A225738.

Table[last = 0; Do[If[n < DivisorSigma[0,n]^(i/10), last = n], {n, 10^4}]; last, {i, 11, 20}]

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

Zdenek Cervenka, Dec 18 2023

Select[Range[1, 10000000], Length[Divisors[#]] - 1 > Sqrt[#] &]

for(k=1,10^6,if(numdiv(k)-1 > sqrtint(k), print1(k,", "))) \\ Joerg Arndt, Jan 06 2024

12 is a term since it has 5 proper divisors (1,2,3,4,6), and 5 > sqrt(12).

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