190736

Appears in sequences

• Janet periodic table of the elements and structured hexagonal diamond numbers. a(n) = A166911(2*n) + A166911(2*n+1).at n=20A167471
• Expansion of 1 / (1 - x - x^3 + x^6) in powers of x.at n=43A193771
• a(n) is the number of permutations pi of [n] that avoid {231,321} so that pi^4 avoids 132.at n=22A368299