Number of derangements of {1,2,...,n} having no adjacent 2-cycles and no adjacent 3-cycles (an adjacent q-cycle is a cycle of the form (i,i+1,i+2,...,i+q-1)).
A177261
Number of derangements of {1,2,...,n} having no adjacent 2-cycles and no adjacent 3-cycles (an adjacent q-cycle is a cycle of the form (i,i+1,i+2,...,i+q-1)).
Terms
- a(0) =1a(1) =0a(2) =0a(3) =1a(4) =7a(5) =35a(6) =218a(7) =1574a(8) =12883a(9) =117956a(10) =1195590a(11) =13295211a(12) =160974037a(13) =2108348871a(14) =29704448652a(15) =447997026724
External references
- oeis: A177261