50316

Appears in sequences

• Fibonacci sequence beginning 4, 17.at n=18A022134
• a(n) = s(1)*t(n) + s(2)*t(n-1) + ... + s(k)*t(n+1-k), where k = floor((n+1)/2), s = A023531, t = (Lucas numbers).at n=22A024319
• a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = A023531, t = (Lucas numbers).at n=21A024882
• Triangle read by rows: T(n,k) is the number of derangements of {1,2,...,n} having genus k (see first comment for definition of genus).at n=38A178514
• Coefficient of x in the reduction by x^2 -> x+1 of the polynomial p(n,x) defined at Comments.at n=19A192966
• Number of -n..n arrays x(0..3) of 4 elements with zero sum and no two neighbors equal.at n=20A199706
• Smallest integer m such that gcd{x | sum of proper divisors of x is m} is equal to n, when there are at least two such x's.at n=4A253302
• Smallest number k such that no n-digit triangular number begins with k.at n=9A254313
• Irregular triangle read by rows: T(n,k) = number of Havender tableaux of height 2 with n columns and k empty squares (n >= 0, 0 <= k <= 2*n).at n=53A259992
• a(n) is the smallest positive integer k such that floor((k + 1)^2/10^n) - floor(k^2/10^n) = 2.at n=4A322667
• Total sum of the left-to-right maxima in all compositions of n.at n=14A336511
• a(n) is the number of perfect powers m^k with k>=3 (A076467) <= 10^n.at n=14A377934