195312500

Appears in sequences

• Hadamard maximal determinant problem: largest determinant of a (real) {0,1}-matrix of order n.at n=21A003432
• a(0) = 1; a(n) = 4*5^(n-1) for n >= 1.at n=12A005054
• a(n) = 5*a(n-2), starting 1,2,4.at n=24A026395
• a(1)=5. For n > 1, a(n) = 4*5^(n-1) = A005054(n).at n=11A110595
• Number of palindromes of length n (in base 5).at n=22A117857
• Number of palindromes of length n (in base 5).at n=23A117857
• a(1)=1, a(n) = (p-1)*a(n-1), if n is even, otherwise a(n) = p*a(n-2), where p = 5.at n=23A133632
• Denominator of Euler(n, 1/5).at n=11A156183
• a(n) = 5*a(n-2) for n > 2; a(1) = 4, a(2) = 5.at n=22A163141
• a(n) = numerator( n^n/(2*n)! ).at n=20A244083
• Numbers k such that the k-th cyclotomic polynomial has a root mod 5.at n=35A245478
• Hypotenuses for which there exist exactly 11 distinct integer triangles.at n=3A290501
• a(n) = phi(n^6) = n^5*phi(n).at n=24A306411
• Numbers k in A020487 with arithmetic derivative k' (A003415) in A020487.at n=24A377383
• Triangle read by rows: T(n,k) is the number of labeled commutative magmas with n elements and k idempotents.at n=19A391482