A269617 Number of length-n 0..6 arrays with no repeated value differing from the previous repeated value by other than plus two, zero or minus 1.
7, 49, 343, 2370, 16218, 110099, 742487, 4979260, 33232924, 220896016, 1463045800, 9659912834, 63605763734, 417796855262, 2738396932202, 17913923467256, 116986307701928, 762789970679730, 4966685787053850, 32298201110078751
Offset: 1
Keywords
Examples
Some solutions for n=6 ..1. .5. .4. .5. .5. .3. .6. .1. .1. .2. .3. .0. .0. .4. .0. .4 ..4. .5. .6. .4. .5. .5. .4. .0. .6. .4. .2. .1. .4. .3. .6. .0 ..0. .6. .2. .6. .0. .4. .5. .5. .1. .5. .1. .6. .4. .3. .3. .2 ..4. .0. .0. .4. .2. .5. .2. .5. .3. .3. .2. .0. .4. .0. .4. .1 ..5. .5. .6. .6. .1. .0. .2. .0. .2. .5. .3. .5. .3. .5. .0. .6 ..4. .4. .1. .4. .3. .0. .4. .1. .6. .3. .5. .3. .1. .0. .3. .3
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A269619.
Formula
Empirical: a(n) = 48*a(n-1) -1001*a(n-2) +11802*a(n-3) -85449*a(n-4) +383292*a(n-5) -1000148*a(n-6) +1185936*a(n-7) +212633*a(n-8) -1064856*a(n-9) -732405*a(n-10) -264438*a(n-11) -65802*a(n-12) -10656*a(n-13) -1071*a(n-14) -54*a(n-15)
Comments