55055

Appears in sequences

• a(n) = 5*(n+1)*binomial(n+4,5)/2.at n=9A027801
• a(n) = 55*(n+1)*binomial(n+4,12).at n=2A027808
• Numbers having four 5's in base 10.at n=10A043512
• a(1) = 5; a(n) = smallest palindromic multiple of a(n-1).at n=3A068666
• Palindromes in which the sum of the internal digits = the sum of the external digits.at n=31A088285
• Palindromic Smith numbers.at n=29A098834
• Triangle T(n,k) read by rows: number of 12312-avoiding matchings on [2n] with exactly k crossings (n >= 1, 0 <= k <= n-1).at n=39A108410
• Triangle T(n,k) read by rows: number of 12312-avoiding matchings on [2n] with exactly k crossings (n >= 1, 0 <= k <= n-1).at n=40A108410
• Dimensions of certain Lie algebra (see reference for precise definition).at n=2A133352
• Numbers whose decimal expansion contains only 0's and 5's.at n=27A169964
• Smith numbers of order 3.at n=17A178213
• Numbers n such that the sum of the distinct prime divisors of n that are congruent to 1 mod 4 equals the sum of the distinct prime divisors congruent to 3 mod 4.at n=34A215949
• Numbers in which each digit equals the sum (mod 10) of the other digits.at n=20A226468
• Least number k such that k^n + n and k^n - n are both prime, or 0 if no such number exists.at n=11A239475
• Triangle read by rows: T(n,r) = binomial(n,r)*binomial(2*n-3*r-4,n-2*r-2)/(n-r-1), n >= 2, r = 0..floor(n/2)-1.at n=46A259097
• Triangle read by rows: T(n,r) = binomial(n,r)*binomial(2*n-3*r-4,n-2*r-2)/(n-r-1), n >= 2, r = 0..floor(n/2)-1.at n=54A259097
• Occurrences of decrease of the probability density P(n) of coprime numbers k,m, satisfying 1 <= k <= a(n) and 1 <= m <= a(n), and a(n) congruent to 1 (mod 2) and a(n) not congruent to 3 (mod 6).at n=21A280879
• Number of 6-leaf rooted trees with n levels.at n=13A290360
• a(n) = 5*(10^(2*n+1) - 1)/9 - 5*10^n.at n=2A332150
• Triangle read by rows: T(n, m) = (n+1-m)*C(2*n+2-m, m)*C(3*n-3*m+2, n-m+1)/(2*n-m+2).at n=23A360546