25200

Appears in sequences

• Highly composite numbers: numbers n where d(n), the number of divisors of n (A000005), increases to a record.at n=23A002182
• Superabundant [or super-abundant] numbers: n such that sigma(n)/n > sigma(m)/m for all m < n, sigma(n) being A000203(n), the sum of the divisors of n.at n=21A004394
• Where records occur in A038548.at n=20A004778
• Number of simplices in barycentric subdivision of n-simplex.at n=4A005461
• The minimal numbers: sequence A005179 arranged in increasing order.at n=44A007416
• Expansion of e.g.f. cos(x)/exp(tanh(x)).at n=9A009115
• a(n) is the concatenation of n and 8n.at n=24A009470
• Least highly composite number divisible by n.at n=24A022404
• Multinomial coefficient n!/ ([n/4]!, [(n+1)/4]!, [(n+2)/4]!, [(n+3)/4]!).at n=10A022917
• a(n) = (n/(n+1)) * lcm(1,2,...,n+1).at n=9A025558
• a(n) = n + (n+1)^2 + (n+2)^3.at n=27A027620
• a(n) = 5^(n-1) - 4*4^(n-1) + 6*3^(n-1) - 4*2^(n-1) + 1 (essentially Stirling numbers of second kind).at n=7A028245
• Triangular array a(n,k) = (1/k)*Sum_{i=0..k} (-1)^(k-i)*binomial(k,i)*i^n; n >= 1, 1 <= k <= n, read by rows.at n=32A028246
• Unary-binary rooted trees with n nodes.at n=7A029766
• Numbers k whose decimal representation, read as a base-12 value and divided by k, yields an integer.at n=20A032555
• Smallest number that is palindromic (with at least 2 digits) in n bases.at n=46A037183
• Triangle T(n,k) (0 <= k <= n) giving number of chains of length k in partially ordered set formed from subsets of n-set by inclusion.at n=34A038719
• a(n) = (n+3)*n!/2.at n=6A038720
• Irrational unitary phi amicable number: numbers b such that uphi(a) = uphi(b) = 2*(a^2-b^2)^(1/2) where uphi = A047994.at n=0A046709
• Triangle read by rows. A generalization of unsigned Lah numbers, called L[4,1].at n=17A048854