116622

Appears in sequences

• A084175 interleaved with 2*A084175.at n=19A138477
• Irregular table read by rows: n-th row lists the 9 n-gonal numbers of a 3 X 3 semimagic square with the smallest magic sum. The terms of each row are arranged in the manner shown in A261816.at n=25A265141
• a(n) = [x^n] Product_{k>=1} (1 + x^k)*(1 - x^(n*k))/((1 - x^k)*(1 + x^(n*k))).at n=30A304627
• Number of degree n polynomials f with all nonzero coefficients equal to 1 such that f(k) is divisible by 3 for all integers k.at n=20A329479
• Number of essentially parallel oriented series-parallel networks with n elements and without multiple unit elements in parallel.at n=13A339289