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A001924 Apply partial sum operator twice to Fibonacci numbers.
(Formerly M2645 N1053)
35
0, 1, 3, 7, 14, 26, 46, 79, 133, 221, 364, 596, 972, 1581, 2567, 4163, 6746, 10926, 17690, 28635, 46345, 75001, 121368, 196392, 317784, 514201, 832011, 1346239, 2178278, 3524546, 5702854, 9227431 (list; graph; refs; listen; history; internal format)
OFFSET

0,3

COMMENTS

Leading coefficients in certain rook polynomials (for n>=2; see p. 18 of the Riordan paper). - Emeric Deutsch (deutsch(AT)duke.poly.edu), Mar 08 2004

A107909(a(n)) = A000225(n) = 2^n - 1. - Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 28 2005

(1, 3, 7, 14,...) = row sums of triangle A141289. - Gary W. Adamson (qntmpkt(AT)yahoo.com), Jun 22 2008

REFERENCES

W. Lang, Problem B-858, Fibonacci Quarterly, 36 (1998), 373-374, ibid. 37 (1999) 183-184.

J. Riordan, Discordant permutations, Scripta Math., 20 (1954), 14-23.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

T. D. Noe, Table of n, a(n) for n=0..500

S. Plouffe, Approximations de S\'{e}ries G\'{e}n\'{e}ratrices et Quelques Conjectures, Dissertation, Universit\'{e} du Qu\'{e}bec \`{a} Montr\'{e}al, 1992.

S. Plouffe, 1031 Generating Functions and Conjectures, Universit\'{e} du Qu\'{e}bec \`{a} Montr\'{e}al, 1992.

Index entries for sequences related to linear recurrences with constant coefficients, signature (3,-2,-1,1).

FORMULA

G.f.: x/((1-x-x^2)*(1-x)^2). Convolution of natural numbers n >= 1 with Fibonacci numbers F(k). a(n)=F(n+4)-(3+n) [ Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de) ]

a(n) = a(n-1)+a(n-2)+n = Fib(n+4)-n-3 = a(n-1)+A000071(n+2) = A001891(n)-a(n-1) = n+A001891(n-1) = A065220(n+4)+1 = A000126(n+1)-1. - Henry Bottomley (se16(AT)btinternet.com), Jan 03 2003

a(n)=sum(k=0, n, sum(i=0, k, F(i))). - Benoit Cloitre (benoit7848c(AT)orange.fr), Jan 26 2003

a(n)=(sqrt(5)/2+1/2)^n*(7*sqrt(5)/10+3/2)+(3/2-7*sqrt(5)/10)*(sqrt(5)/2-1/2)^n*(-1)^n-n-3 - Paul Barry (pbarry(AT)wit.ie), Mar 26 2003

a(n)=sum(k=0, n, F(k)*(n-k)) - Benoit Cloitre (benoit7848c(AT)orange.fr), Jun 07 2004

a(n) - a(n-1) = A101220(1,1,n). - Ross La Haye (rlahaye(AT)new.rr.com), May 31 2006

F(n) + a(n-3) = A133640(n). - Gary W. Adamson (qntmpkt(AT)yahoo.com), Sep 19 2007

a(n)=Sum_{k=1..n}{C(n-k+2,k+1)}, with n>=0. - Paolo P. Lava (paoloplava(AT)gmail.com), Apr 16 2008

MAPLE

A001924:=-1/(z**2+z-1)/(z-1)**2; [Conjectured by S. Plouffe in his 1992 dissertation.]

The conjecture by Simon Plouffe needs to have the numerator changed from -1 to z. (* RGWv *)

MATHEMATICA

Join[{b=0}, a=0; Table[c=b+a+n; a=b; b=c, {n, 1, 60}]] [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Dec 10 2008]

f[n_] := Fibonacci[n + 4] - 3 - n; Array[f, 32, 0] (* Or *)

Accumulate@ Accumulate@ Fibonacci@ Range[0, 31] (* Or *)

a[n_] := a[n] = a[n - 1] + a[n - 2] + n; a[0] = 0; a[1] = 1; Array[a, 32, 0]  (* Or )

gf = x/(1 - 3 x + 2 x^2 + x^3 - x^4); CoefficientList[ Series[ gf, {x, 0, 31}], x] (* RGWv *)

PROG

(PARI) a(n)=fibonacci(n+4)-n-3 \\ Charles R Greathouse IV, Feb 24, 2011

CROSSREFS

Cf. A000045, A001891, A133640, A141289.

Right-hand column 4 of triangle A011794.

Sequence in context: A008646 A036830 A014153 * A079921 A014168 A132109

Adjacent sequences:  A001921 A001922 A001923 * A001925 A001926 A001927

KEYWORD

nonn,easy,nice

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

EXTENSIONS

Better description 1/97.

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Last modified February 15 21:56 EST 2012. Contains 205860 sequences.