A058966 a(3) = 1, otherwise a(n) = n*2^(n-3) - 2^(n-2) - 2.

1, 2, 10, 30, 78, 190, 446, 1022, 2302, 5118, 11262, 24574, 53246, 114686, 245758, 524286, 1114110, 2359294, 4980734, 10485758, 22020094, 46137342, 96468990, 201326590, 419430398, 872415230, 1811939326, 3758096382, 7784628222

Offset

3,2

References

B. Elspas, The theory of multirail cascades, in A. Mukhopadhyay, ed., Recent Developments in Switching Theory, Ac. Press, 1971, Chap. 8, see esp. p. 361 (S_1(n)).

Links

Harry J. Smith, Table of n, a(n) for n = 3...200

Index entries for linear recurrences with constant coefficients, signature (5,-8,4).

Formula

From Colin Barker, Mar 23 2012: (Start)

a(n) = 5*a(n-1)-8*a(n-2)+4*a(n-3) for n>6.

G.f.: x^3*(1-3*x+8*x^2-8*x^3)/((1-x)*(1-2*x)^2). (End)

Mathematica

Join[{1}, Table[n*2^(n-3)-2^(n-2)-2, {n, 4, 40}]] (* or *) LinearRecurrence[ {5, -8, 4}, {1, 2, 10, 30}, 40] (* Harvey P. Dale, Dec 22 2019 *)

Prog

(PARI) { for (n = 3, 200, write("b058966.txt", n, " ", abs(n*2^(n-3)-2^(n-2)-2)); ) } \\ Harry J. Smith, Jun 24 2009

Crossrefs

Sequence in context: A051667 A106355 A120546 * A058967 A355775 A234471

Adjacent sequences: A058963 A058964 A058965 * A058967 A058968 A058969

Keyword

nonn,easy

Author

N. J. A. Sloane, Jan 14 2001

Status

approved