20860
domain: N
Appears in sequences
- Cubes written in base 9.at n=23A004639
- a(n) = (n+1)*(n^2+n+2)/2; g.f.: (1 + 2*x^2) / (1 - x)^4.at n=34A006000
- a(n) = floor( tan(m*Pi/2) ), where m = 1 - 2^(-n).at n=14A024810
- Number of words of length 2n in the 10 transpositions of S[5] equivalent to the identity.at n=2A029698
- Number of words of length 6 in the n(n-1)/2 transpositions of S[ n ] equivalent to the identity.at n=4A029700
- Engel expansion for tan(1).at n=7A084652
- Elements of A065607 from primitive triples.at n=24A120693
- Number of d+/d- diagonally convex polyominoes with n cells.at n=9A187276
- 37-gonal numbers: a(n) = n*(35*n-33)/2.at n=35A282852
- Relative of Hofstadter Q-sequence: a(n) = max(0, n+20830) for n <= 0; a(n) = a(n-a(n-1)) + a(n-a(n-2)) + a(n-a(n-3)) for n > 0.at n=31A283887
- a(n) = (prime(n)+1) * prime(n+1).at n=33A345727
- The fifth term of the greedy B_n set of natural numbers.at n=33A369817