18231

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 45.at n=41A031543
• Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 45.at n=2A031723
• Numerators of continued fraction convergents to sqrt(166).at n=9A041306
• Numbers k such that the decimal digits of phi(k) are a permutation of those of k.at n=22A115921
• Integers k such that 0 < |k^5 - m^2| <= k^(3/2) for some integer m.at n=12A116884
• Column 0 of the matrix log of triangle A118180, after term in row n is multiplied by n: a(n) = n*[log(A118180)](n,0), where A118180(n,k) = 3^(k*(n-k)).at n=6A118184
• Numbers k with property that 19*k + {2,4,8,10} are two pairs of consecutive twin primes.at n=6A152926
• Half the number of n X n symmetric binary matrices with no element equal to a strict majority of its king- and knight-move neighbors.at n=7A190631
• Values x for record minima of the positive distance d between the square of an integer y and the fifth power of a positive integer x such that d = y^2 - x^5 (x <> k^2 and y <> k^5).at n=21A198444
• Number of (n+1) X (4+1) 0..2 arrays with the minimum plus the upper median equal to the lower median plus the maximum in every 2 X 2 subblock.at n=6A235880
• Number of (n+1) X (7+1) 0..2 arrays with the minimum plus the upper median equal to the lower median plus the maximum in every 2 X 2 subblock.at n=3A235883
• Numbers k such that k![12]+2 is prime, where k![12] is the twelve-fold multifactorial.at n=35A283594
• Number of n-digit biquanimous strings using digits {0,1,...,8}.at n=5A288692