A269406 Number of length-n 0..5 arrays with no repeated value greater than or equal to the previous repeated value.
6, 36, 210, 1215, 6960, 39560, 223320, 1253190, 6995660, 38870136, 215074596, 1185563746, 6512894520, 35666937840, 194765568024, 1060744346079, 5762980508994, 31239002042780, 168977143019910, 912220049428041
Offset: 1
Keywords
Examples
Some solutions for n=6 ..5. .0. .4. .3. .3. .1. .2. .4. .4. .1. .0. .0. .2. .2. .2. .0 ..2. .5. .2. .1. .5. .3. .5. .4. .0. .5. .3. .1. .3. .4. .5. .4 ..1. .0. .4. .5. .2. .0. .4. .2. .5. .2. .3. .5. .5. .1. .2. .2 ..2. .5. .4. .2. .4. .3. .0. .0. .5. .5. .1. .2. .4. .4. .5. .4 ..0. .4. .5. .0. .4. .5. .1. .0. .1. .4. .3. .1. .3. .5. .2. .5 ..3. .1. .3. .3. .3. .1. .0. .5. .2. .1. .0. .0. .1. .3. .2. .1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A269409.
Formula
Empirical: a(n) = 30*a(n-1) -360*a(n-2) +2090*a(n-3) -4905*a(n-4) -5076*a(n-5) +41160*a(n-6) -9900*a(n-7) -151875*a(n-8) -6250*a(n-9) +300000*a(n-10) +281250*a(n-11) +78125*a(n-12)
Comments