A011820 Number of M-sequences m_0,...,m_4 with m_1 < n.

2, 6, 32, 203, 1144, 5345, 20926, 70506, 209746, 562727, 1384758, 3167606, 6807620, 13863904, 26941700, 50245591, 90358146, 157312324, 266040452, 438299013, 705186944, 1110395771, 1714352818, 2599444040, 3876530866

Offset

0,1

References

S. Linusson, The number of M-sequences and f-vectors, Combinatorica, 19 (1999), 255-266.

Links

T. D. Noe, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (11,-55,165,-330,462,-462,330,-165,55,-11,1).

Formula

a(n) = ( 4*n^10 +61*n^9 +408*n^8 +1722*n^7 +6132*n^6 +18333*n^5 +41072*n^4 +88748*n^3 +133824*n^2 +193536*n +241920 )/120960. - Frank Ellermann

G.f.: -x*(x^10 -11*x^9 +53*x^8 -147*x^7 +268*x^6 -298*x^5 +341*x^4 -149*x^3 +76*x^2 -16*x +2) / (x-1)^11. - Colin Barker, Feb 15 2014

Prog

(PARI) a(n)=n*(4*n^9+61*n^8+408*n^7+1722*n^6+6132*n^5+18333*n^4+41072*n^3 +88748*n^2 +133824*n+193536)/120960+2 \\ Charles R Greathouse IV, Dec 08 2011

Crossrefs

Cf. A011819-A011825, A011828.

Sequence in context: A055596 A318976 A109572 * A206300 A224884 A361354

Adjacent sequences: A011817 A011818 A011819 * A011821 A011822 A011823

Keyword

nonn,easy

Author

Svante Linusson (linusson(AT)math.kth.se)

Status

approved