A011821 Number of M-sequences m_0,...,m_5 with m_1 < n.

2, 7, 64, 877, 10742, 102050, 753994, 4486435, 22285884, 95264798, 359074648, 1216716022, 3763991016, 10763615106, 28741372964, 72261453121, 172248589406, 391536067037, 852876877928, 1787799809335, 3619382778994

Offset

1,1

Comments

Apparently a polynomial of degree 15: n^15/32659200 etc., compare A011829. [Frank Ellermann]

References

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

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Index entries for linear recurrences with constant coefficients, signature (16,-120,560,-1820,4368,-8008,11440,-12870,11440,-8008,4368,-1820,560,-120,16,-1).

Formula

G.f.: -x*(x^15 -16*x^14 +118*x^13 -532*x^12 +1648*x^11 -3712*x^10 +5776*x^9 -12080*x^8 -2775*x^7 -21034*x^6 -3582*x^5 -4110*x^4 +427*x^3 -192*x^2 +25*x -2)/(x -1)^16. [Colin Barker, Sep 18 2012]

Mathematica

CoefficientList[Series[- (x^15 - 16 x^14 + 118 x^13 - 532 x^12 + 1648 x^11 - 3712 x^10 + 5776 x^9 - 12080 x^8 - 2775 x^7 - 21034 x^6 - 3582 x^5 - 4110 x^4 + 427 x^3 - 192 x^2 + 25 x - 2)/(x - 1)^16, {x, 0, 50}], x] (* Vincenzo Librandi, Oct 15 2013 *)
LinearRecurrence[{16, -120, 560, -1820, 4368, -8008, 11440, -12870, 11440, -8008, 4368, -1820, 560, -120, 16, -1}, {2, 7, 64, 877, 10742, 102050, 753994, 4486435, 22285884, 95264798, 359074648, 1216716022, 3763991016, 10763615106, 28741372964, 72261453121}, 30] (* Harvey P. Dale, Nov 24 2019 *)

Crossrefs

Cf. A011819-A011825, A011829.

Sequence in context: A181030 A006506 A346781 * A366705 A117263 A046855

Adjacent sequences: A011818 A011819 A011820 * A011822 A011823 A011824

Keyword

nonn,easy

Author

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

Status

approved