20883

Appears in sequences

• Number of partitions of n into parts not a multiple of 7. Also number of partitions with at most 6 parts of size 1 and differences between parts at distance 9 are greater than 1.at n=39A035985
• Numbers whose base-12 representation has exactly 5 runs.at n=2A043654
• Expansion of g.f.: Product_{n>0} 1/(1 - 2^(n-1)*x^n).at n=12A075900
• Number of base 31 n-digit numbers with adjacent digits differing by one or less.at n=7A126385
• Number of n X 7 binary arrays without the pattern 0 1 diagonally, vertically or antidiagonally.at n=29A188864
• Number of set partitions of {1, ..., n} that avoid enhanced 4-crossings (or enhanced 4-nestings).at n=9A192855
• Number of 2n-bead necklaces labeled with numbers 1..4 not allowing reversal, with neighbors differing by exactly 1.at n=12A208723
• Numbers k such that 4*10^k - 89 is prime.at n=18A290475
• Number of ways to choose a strict composition of each part of an integer partition of n.at n=16A336141