1396755360
domain: N
Appears in sequences
- a(1)=1; for n > 1, a(n) is the smallest number with the same number of divisors as 2*a(n-1).at n=35A019505
- LCM of numbers <= n and having a factor in common with n.at n=41A066574
- LCM of numbers m such that 1 <= m <= n, m has a common factor with n, but m does not divide n.at n=41A066575
- Product of terms in n-th row of triangle A094275.at n=5A094278
- Least number k such that the number of divisors of k which are < log(k) equals n.at n=21A096001
- Largest highly composite number <= 2*a(n-1).at n=34A135614
- a(n) is the smallest integer k such that n*k is the smallest multiple of k with twice as many divisors as k, or 0 if no such number is possible.at n=18A139315
- Highly composite numbers (A002182) whose following highly composite number is at least 3/2 times greater.at n=26A162936
- Proper GA1 numbers: terms of A197638 with at least three prime divisors counted with multiplicity.at n=2A201557
- Least number with the same prime signature as the n-th Fibonacci number: a(n) = A046523(A000045(n)).at n=71A278245
- Bi-unitary superabundant numbers: numbers n such that bsigma(n)/n > bsigma(m)/m for all m < n, where bsigma is the sum of the bi-unitary divisors function (A188999).at n=20A292984
- Bi-unitary highly composite numbers: where the number of bi-unitary divisors of n (A286324) increases to a record.at n=24A293185
- Highly composite numbers (A002182) with a record number of largely composite numbers (A067128) having the same number of divisors.at n=6A308532
- a(n) is the least k such that A213636(k) = n.at n=20A326778
- Nonexponential superabundant numbers: numbers m such that nesigma(m)/m > nesigma(k)/k for all k < m, where nesigma(m) is the sum of nonexponential divisors of m (A160135).at n=24A348630
- a(1) = 1; for n > 1, a(n) is the smallest number with at least as many divisors as 2*a(n-1).at n=35A350049
- Regular triangle read by rows, T(n,k) is the least integer m such that sigma(m)/m is greater than n + (k-1)/n.at n=11A352281
- Highly composite numbers that are one more than a prime number.at n=27A352634
- Smallest highly composite number beginning with n.at n=12A353216
- Square array read by antidiagonals: row n lists numbers whose maximal frequency in a fixed row of A036038 (or A078760) is equal to n, i.e., numbers m such that A376663(m) = n.at n=14A376667