24090

Appears in sequences

• Number of rooted toroidal maps with 2 faces, n vertices and no isthmuses.at n=7A006469
• a(n) = n*(n^2 - 1)*(n + 2)*(n^2 + 4*n + 6)/72.at n=10A054563
• a(n) = floor(e^n mod n^e).at n=43A066433
• Triangular numbers with sum of digits = 15.at n=30A068130
• Number of 5 X 5 pandiagonal magic squares with sum n.at n=8A070212
• Rearrangement of triangular numbers such that the sum of two consecutive terms is a palindrome.at n=27A082980
• Numbers of the form prime(n) + prime(n+1) - 2 that are also triangular numbers, T(k) = k(k+1)/2.at n=20A110891
• Hexagonal numbers for which the sum of the digits is also a hexagonal number.at n=23A117062
• Hexagonal numbers for which both the sum of the digits and the product of the digits are also hexagonal numbers.at n=13A117064
• Triangular numbers for which the sum of the digits is a hexagonal number.at n=43A117309
• Hexagonal numbers divisible by 6.at n=37A117794
• Hexagonal numbers (A000384) which are sum of 2 other hexagonal numbers > 0.at n=20A133215
• Triangle read by rows: row n gives coefficients of expansion of q-tangent number T_{2n+1}(q) in powers of q.at n=44A143194
• Triangle read by rows: row n gives coefficients of expansion of q-tangent number T_{2n+1}(q) in powers of q.at n=51A143194
• Triangular numbers which are sums of 6 consecutive primes.at n=6A173423
• Triangular arithmetic on half-squares: b(n)*(b(n) - 1)/2 where b(n) = floor(n^2/2).at n=21A227970
• a(n) is the smallest nonnegative integer such that a(n)! contains a string of exactly n consecutive 9's.at n=9A254717
• Numbers k such that 1/phi(x) + 1/phi(y) = 1/phi(k), for some x + y = k and phi(k) is the Euler totient function of k.at n=26A279621
• The first of two consecutive triangular numbers the sum of which is equal to the sum of two consecutive prime numbers.at n=16A298462
• Expansion of (-5*(9 - 6*x + 2*x^2))/(-1 + x)^3.at n=42A331190