2778300

Appears in sequences

• a(n) is the number of sets of natural numbers [a,b,c,d,e] that can be produced with the numbers [0..n] such that the values of all the distinct parenthesized expressions of a-b-c-d-e are different.at n=20A054026
• Triangle of coefficients of (x+1)*(x+3)*(x+6)*...*(x+n(n+1)/2).at n=34A128813
• Triangle read by rows of products of Stirling numbers of the second kind (A008277): a(n,k) = S(n,k) S(n+1,k+1).at n=41A187557
• (n-1)-st elementary symmetric function of the first n triangular numbers.at n=6A203157
• Product_{n>=1} 1 + a(n)*x^n = Sum_{n=-oo..oo} x^(n^2) = theta_3(x).at n=25A342223
• Primitives exponential abundant numbers that are not primitives exponential unitary abundant.at n=22A391086
• Primitive exponential Zumkeller numbers that are not primitive exponential unitary Zumkeller numbers.at n=24A391091