28455

Appears in sequences

• n*(1+3*n+6*n^2)/2.at n=21A115519
• Riordan matrix (1/(x+sqrt(1-4x)),(1-sqrt(1-4x))/(2(x+sqrt(1-4x)))).at n=46A188513
• Triangle of coefficients of polynomials v(n,x) jointly generated with A210751; see the Formula section.at n=52A210752
• Numbers such that sigma(phi(tau(n)))=tau(phi(sigma(n))).at n=23A226119
• Number of partitions of n such that the number of parts having multiplicity 1 is not a part and the number of distinct parts is a part.at n=49A241443
• Solution of the complementary equation a(n) = a(n-1) + a(n-2) + 2*b(n-1) - b(n-2) - 2, where a(0) = 1, a(1) = 2, b(0) = 3, and (a(n)) and (b(n)) are increasing complementary sequences.at n=18A294565