24200

Appears in sequences

• Sum of squares of numbers in row n of array T given by A026780.at n=7A027253
• Number of n-node rooted identity trees of height at most 7.at n=17A038086
• Numbers k such that k^2 + 1 is composite and phi(k^2 + 1) == 0 (mod k).at n=35A067519
• Transform of n^3 by the Riordan array (1/(1-x^2), x).at n=20A105636
• A symmetrical triangle based on Stirling numbers of the second kind :q=2;t(n,m,q)=If[m == 0 Or m == n, 1, If[Floor[n/2] greater than or equal to m, StirlingS2[ n, m]*q^m, StirlingS2[n, n - m]*q^(n - m)]].at n=48A174545
• A symmetrical triangle based on Stirling numbers of the second kind :q=2;t(n,m,q)=If[m == 0 Or m == n, 1, If[Floor[n/2] greater than or equal to m, StirlingS2[ n, m]*q^m, StirlingS2[n, n - m]*q^(n - m)]].at n=51A174545
• a(n) = n*(n+1)*(5*n+1)/3.at n=24A174814
• Numbers of the form p^3*q^2*r^2 where p, q, and r are distinct primes.at n=12A179695
• E.g.f.: 1 + Sum_{n>=1} x^n * Product_{k=1..n} (exp(k*x)-1)/(exp(x)-1).at n=5A196194
• a(n) = n^4/8 if n is even, a(n) = (n^2-1)^2/8 if n is odd.at n=21A212892
• Triangular array read by rows. T(n,k) = A008277(n,k)*2^k; n >= 1, 1 <= k <= n.at n=38A227450
• Number of perfect matchings in graph C_3 x C_{2n}.at n=4A231087
• Combined weight, as defined at A244094, of the distinct-parts partitions of n.at n=28A234924
• Positive integers, c, such that there are more than two solutions to the equation a^2 + b^3 = c^4, with a, b > 0.at n=20A242381
• Records in A072994.at n=42A252594
• Sum of cubes of the first n even numbers (A016743).at n=10A254371
• a(n) is the smallest number satisfying a(n)^2+1 = p(n)*q(n), p(n) < q(n) both prime, such that q(n+1)/p(n+1) < q(n)/p(n) with the initial condition q(1)/p(1) < 3/2.at n=12A261803
• Numbers k such that k and k^2 are the sums of two nonzero squares in exactly two ways.at n=42A273293
• a(n) = A008412(n-1) + A008412(n-2) for n>1, a(0)=0, a(1)=1.at n=18A287324
• Sum of all the parts in the partitions of n into 6 squarefree parts.at n=44A308903