87360

Appears in sequences

• Number of n-colored connected graphs on n labeled nodes.at n=5A002032
• Unitary perfect numbers: numbers k such that usigma(k) - k = k.at n=3A002827
• Unitary harmonic numbers (those for which the unitary harmonic mean is an integer).at n=24A006086
• a(n) = number of (s(0), s(1), ..., s(n)) such that s(i) is a nonnegative integer and |s(i) - s(i-1)| <= 1 for i = 1,2,...,n, s(0) = 2, s(n) = 6. Also a(n) = T(n,n-4), where T is the array in A026323.at n=9A026329
• A triangle of numbers related to triangle A030527.at n=24A049374
• Expansion of e.g.f.: x^2*(exp(x)-1)^4.at n=8A052792
• Cusp form of weight 13/2 associated to the unique cusp form of weight 12 under Shimura correspondence.at n=55A054891
• Smallest k such that d(phi(k)) - phi(d(k)) = -n, where d(k) = A000005(k) and phi(k) = A000010(k).at n=11A078151
• Row sums in A083167.at n=39A083170
• Numbers that can be expressed as the difference of the squares of primes in exactly ten distinct ways.at n=4A092006
• UO-sigma multiperfect numbers: n such that A069184(n)/n is an integer.at n=7A092356
• If f[x]=(sum of unitary-proper divisors of x)=A063919[x] is iterated, the iteration may lead to a fixed point which is either 0 or belongs to A002827, a unitary-perfect-number >1: 6,60,90,87360... Sequence gives initial values for which the iteration ends in 87360, the 4th unitary perfect number.at n=0A098186
• Number of monic irreducible polynomials of degree 3 in GF(2^n)[x].at n=5A115489
• Amicable triples. Sequence gives sigma values: A125490(n) + A125491(n) + A125492(n).at n=3A137231
• Triangle T(n,k) = binomial(2*n,k) *binomial(2*n-2*k,n-k), read by rows; 0<=k<=n.at n=41A142243
• A partition product with biggest-part statistic of Stirling_1 type (with parameter k = -2) as well as of Stirling_2 type (with parameter k = -2), (triangle read by rows).at n=32A157400
• a(n) = 20*a(n-1) - 64*a(n-2) for n > 1; a(0) = 21, a(1) = 340.at n=3A166914
• Numbers k such that bigomega(k)^omega(k) > k.at n=37A177871
• a(n) is the smallest n-perfect number of the form 2^(n+1)*L, where L is an odd number with exponents <= n in its prime power factorization, and a(n)=0 if no such n-perfect number exists.at n=4A178785
• Number T(n,k) of permutations on n elements with exactly k 3-cycles; triangle read by rows.at n=19A186526