23268

Appears in sequences

• Numbers that are the sum of 9 positive 9th powers.at n=17A003398
• Number of ways to place 3 nonattacking zebras on a 3 X n board.at n=17A172221
• G.f. satisfies: A(x) = exp( Sum_{n>=1} A(x)^n * A(x^n) * x^n/n ).at n=8A198413
• Partial sums of A243980.at n=26A244050
• Numbers k such that there is no prime between the k-th perfect power and the (k+1)-st perfect power.at n=9A274605
• E.g.f. S(x,y) = Integral C(x,y)*C(y,x) dx such that C(x,y)^2 - S(x,y)^2 = 1 and C(y,x) = 1 + Integral S(y,x)*C(x,y) dy, where S(x,y) = Sum_{n>=0} Sum_{k=0..n} T(n,k) * x^(2*n+1-2*k)*y^(2*k)/(2*n+1)!, as a triangle of coefficients T(n,k) read by rows.at n=13A322730
• Number of ways to write n as an ordered sum of 7 primes.at n=31A340963
• Number of regions in a graph of n adjacent rectangles in a row with all possible diagonals drawn, as in A306302, but without the rectangles' edges which are perpendicular to the row.at n=18A369175