26580

Appears in sequences

• Number of unsensed planar maps with n edges and without loops or isthmuses.at n=11A006399
• First of triples of consecutive happy numbers, i.e., the first of three consecutive integers each of which is a happy number (A007770).at n=26A072494
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (0, 1, -1), (0, 1, 0), (1, 0, 1), (1, 1, 1)}.at n=7A151204
• Number of (w,x,y,z) with all terms in {1,...,n} and w+x=|x-y|+|y-z|.at n=37A212676
• Unchanging value maps: number of n X 2 binary arrays indicating the locations of corresponding elements unequal to no horizontal, diagonal or antidiagonal neighbor in a random 0..2 n X 2 array.at n=9A219136
• Wiener index of the n-Hanoi graph.at n=3A290004
• Growth series for group with presentation < S, T : S^2 = T^3 = (S*T)^7 = 1 >.at n=39A298805
• Number of partitions of n containing a prime number of primes and an arbitrary number of nonprimes.at n=42A344677
• a(n) = Sum_{k=0..n} 4^(n-k) * binomial(n+k-1,k) * binomial(k/2,n-k).at n=7A378554