17578125

Appears in sequences

• Smallest label f(T) given to a rooted tree T with n nodes in Matula-Goebel labeling.at n=31A005517
• a(n) = n*5^n.at n=9A036291
• Reciprocal of n terminates with an infinite repetition of digit 8. Multiples of 10 are omitted.at n=4A064567
• a(n) = (2*n+1)*5^(2*n+1).at n=4A072172
• 5th binomial transform of (0,0,1,0,0,0, ...).at n=10A081135
• a(n) = 5^(n-1)*n*(n+1)/2.at n=9A084902
• Denominators of Egyptian fraction for Pi/16 based on Machin's formula.at n=8A157332
• Number of nX3 array permutations with each element not moved or moved diagonally or antidiagonally by one.at n=10A189274
• Expansion of g.f. (1+4*x)/(1-5*x).at n=10A270567
• Number of set partitions of [n] such that i-j is a multiple of nine for all i,j belonging to the same block.at n=29A275076
• Hypotenuses for which there exist exactly 9 distinct integer triangles.at n=7A290500
• Triangle read by rows: T(0,0) = 1; T(n,k) = 5*T(n-1,k) + T(n-2,k-1) for k = 0..floor(n/2); T(n,k)=0 for n or k < 0.at n=44A305837
• Odd numbers of the form p^(1+4k) * r^2, where p is prime of the form 1+4m, k > 0, r > 1, and gcd(p,r) = 1.at n=32A386428