257040

Appears in sequences

• a(n) = n*(n+1)*(n+2)^2/6.at n=34A004320
• Unitary harmonic numbers (those for which the unitary harmonic mean is an integer).at n=31A006086
• Number of trivalent bipartite labeled graphs with 2n labeled nodes.at n=2A006714
• Absolute value of determinant of n X n matrix whose entries are the integers from 1 to n^2 spiraling inward, starting in a corner.at n=5A023999
• Number of labeled pure 2-complexes on n nodes (0-simplexes) with 5 2-simplexes and 8 1-simplexes.at n=13A054559
• Infinitary harmonic numbers: harmonic mean of infinitary divisors is an integer.at n=26A063947
• Triangle, read by rows, where the g.f. of row n, R_n(x), is a polynomial of degree n that satisfies: [x^k] R_{n+1}(x) = [x^k] (1 + x*R_n(x))^(n+1) for k=0..n+1, with R_0(x) = 1.at n=50A108990
• Triangle read by rows: T(n,k) = the number of ascending runs of length k in the permutations of [n] for k <= n.at n=38A122843
• a(n)=(A002866(n+1) - A036691(n))/192.at n=8A131206
• Smallest size of which there are n tatami-free rooms.at n=32A165764
• Least number k such that sigma(k) >= 2^n.at n=19A172516
• Position of records in A067513.at n=33A202727
• Numbers k such that k and k^3 are sums of two twin primes.at n=35A213811
• Integer areas A of integer-sided cyclic quadrilaterals such that the circumradius is of prime length.at n=42A230136
• Records in A187202 by index.at n=45A242393
• Number of connected trivalent bipartite labeled graphs with 2n labeled nodes.at n=2A246599
• Highly composite numbers of class 4 (see comment in A275239).at n=28A275242
• Tri-unitary harmonic numbers: numbers k such that the harmonic mean of the tri-unitary divisors of k is an integer.at n=27A335387
• Numbers that are both infinitary and noninfinitary harmonic numbers.at n=3A348922
• Positions of records in A356018, i.e., integers whose number of evil divisors sets a new record.at n=37A356020