A107601 Column 6 of array illustrated in A089574 and related to A034261.

7, 71, 350, 1204, 3329, 7936, 16981, 33452, 61719, 107953, 180620, 291056, 454129, 688994, 1019947, 1477384, 2098871, 2930331, 4027354, 5456636, 7297553, 9643876, 12605633, 16311124, 20909095, 26571077, 33493896, 41902360, 52052129

Offset: 0

Author

Alford Arnold, May 27 2005

Keywords

• nonn

Comments

Column six is associated with the following partitions: 66, 552, 443, 4422, 3332, 33222 and 222222.

Examples

			a(1) = 7 because there are 3 permutations of 443 and 4 permutations of 3332.
a(2) = 71 because there are 1 + 3 + 18 + 6 + 32 + 10 + 1 permutations of the associated partitions.
		

Links

• Index entries for linear recurrences with constant coefficients, signature (8,-28,56,-70,56,-28,8,-1). [From _R. J. Mathar_, Jun 26 2010]

Crossrefs

Cf. A107600.

Formula

a(n) = A107601(10+n,5+n) = n*(1384+4683*n^2+2142*n+2*n^6+651*n^4+63*n^5+2835*n^3)/1680. a(n)= +8*a(n-1) -28*a(n-2) +56*a(n-3) -70*a(n-4) +56*a(n-5) -28*a(n-6) +8*a(n-7) -a(n-8). G.f.: x*(7+15*x-22*x^2+11*x^4-6*x^5+x^6)/(x-1)^8. [From R. J. Mathar, Jun 26 2010]

Extensions

Extended beyond a(5) by R. J. Mathar, Jun 26 2010