5322240

Appears in sequences

• Expansion of e.g.f. x*(1 - 2*x - sqrt(1-4*x))/2.at n=8A052711
• Expansion of e.g.f. x*(1 - sqrt(1 - 4*x))/2.at n=8A052717
• Fourth (unsigned) column sequence of triangle A062140 (generalized a=4 Laguerre).at n=5A062261
• Denominators in expansion of (exp(x)-1)^3.at n=14A065975
• a(n) = permanent of a bordered n X n (1,-1)-matrix with the following property: the elements on the border are 1; if we concatenate the rows of the matrix to form a vector v of length n^2, v_i = -1 if i is not a prime. The border of a matrix consists of the first and the last row and the first and the last column.at n=9A114530
• Numbers k for which sigma(k)/k - 3/7 is an integer.at n=4A218410
• Integers k such that numerator and denominator of sigma(k)/k are both prime.at n=29A247086
• Solutions y to the negative Pell equation y^2 = 72*x^2 - 73728 with x,y >= 0.at n=6A281238
• a(n) is the smallest number m with exactly n divisors that are Zuckerman numbers, or -1 if there is no such m.at n=37A335038
• Integers whose number of divisors that are Zuckerman numbers sets a new record.at n=27A340638
• Triangle read by rows: T(n, k) = binomial(n, k) * Pochhammer(n, k).at n=41A370706