A179581 Number of permutations of 1..n+6 with the number moved left exceeding the number moved right by n or more

1823, 6095, 19389, 59939, 182284, 549268, 1646856, 4925510, 14716637, 43963245, 131367367, 392727885, 1174712338, 3515619386, 10526412826, 31531005592, 94480820299, 283184511707, 848966332193, 2545573595015, 7633751214888

Offset

1,1

Comments

Recurrence would also extend to an a(0) if the definition were made to exclude the identity permutation

Links

R. H. Hardin, Table of n, a(n) for n=1..45

Formula

Empirical: a(n)=14*a(n-1)-85*a(n-2)+294*a(n-3)-639*a(n-4)+906*a(n-5)-839*a(n-6)+490*a(n-7)-164*a(n-8)+24*a(n-9) ; G.f.: -x*(1823-19427*x+89014*x^2-229394*x^3+364170*x^4-365192*x^5+226176*x^6-79168*x^7+12000*x^8) / ( (-1+3*x)*(2*x-1)^3*(x-1)^5 ).

Crossrefs

Sequence in context: A218104 A171349 A256076 * A230052 A234222 A233813

Adjacent sequences: A179578 A179579 A179580 * A179582 A179583 A179584

Keyword

nonn

Author

R. H. Hardin, g.f. from R. J. Mathar in the Sequence Fans Mailing List, Jul 19 2010

Status

approved