Sequences

Number of paraffins (see Losanitsch reference for precise definition).

a(n) = n^2*(n^2 - 1)/4.

a(0) = 1, a(1) = 2, a(n) = 4*a(n-1) - 2*a(n-2), n >= 2.

a(n) = binomial(3*n+1,n)/(n+1).

a(n+1) = (n+1)*a(n) + Sum_{k=1..n-1} a(k)*a(n-k).

Nim product 2*n.

The nim value for the game of Sym with n tails and 1 head.

Nim product 2^n * 2^n.

List of periods for game of Third One Lucky.

Remoteness number of n in Simon Norton's game of Tribulations.

Suspense numbers for Tribulations.

The game of contours.

Sprague-Grundy (or Nim) values for the game of Maundy cake on an n X 1 sheet.

Number of unlabeled mating digraphs with n nodes.

Number of labeled mating graphs with n nodes. Also called point-determining graphs.

Number of labeled mating digraphs with n nodes.

Number of column-convex polyominoes with perimeter n.

Number of directed column-convex polyominoes with perimeter 2n+2.

Weight distribution of [ 128,99,8 ] 4th-order Reed-Muller code RM(4,7).

Numbers k such that the k-th tetrahedral number k*(k+1)*(k+2)/6 is palindromic.

Palindromic tetrahedral numbers.

Erroneous version of A016054.

Numbers k such that (14^k - 1)/13 is prime.

Numbers k such that (15^k - 1)/14 is prime.

Numbers k such that (17^k - 1)/16 is prime.

Numbers k such that (19^k - 1)/18 is prime.

Primitive pseudoperfect numbers.

Weird numbers: abundant (A005101) but not pseudoperfect (A005835).

Odd primitive abundant numbers.

Primitive nondeficient numbers.

a(n) = Sum_{i=0..n} (n!/(n-i)!)^2.

a(n+1) = (n^2 - 1)*a(n) + n + 1.

The nim-square of n.

A traffic light problem: expansion of 2/(1 - 3*x)^3.

a(n) = 4^(n-4)*(n-1)*(n-2)*(n-3).

Sum of orders of all 2 X 2 matrices with entries mod n.

Total number of odd entries in first n rows of Pascal's triangle: a(0) = 0, a(1) = 1, a(2k) = 3*a(k), a(2k+1) = 2*a(k) + a(k+1). a(n) = Sum_{i=0..n-1} 2^wt(i).

Number of entries in n-th row of Pascal's triangle not divisible by 3.

Number of entries in first n rows of Pascal's triangle not divisible by 3.

Numbers k such that k and k+1 have the same number of distinct prime divisors.

Smallest number of additive persistence n.

Square hex numbers.

Number of magic squares of order n composed of the numbers from 1 to n^2, counted up to rotations and reflections.

a(n) = a(n-1) + 2*a(n-2) - a(n-3), with a(0) = a(1) = 0, a(2) = 1.

a(n) = 2*a(n-1) + a(n-2) - a(n-3), with a(0) = a(1) = 0, a(2) = 1.

Primes with consecutive (ascending) digits.

Number of topologies on n labeled points satisfying the T_4 axiom.

Number of topologies on n labeled points satisfying axioms T_0-T_4.

Number of connected labeled T_4-topologies with n points.

Number of connected labeled T_0-T_4-topologies with n points.