login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A026070 a(n) = number of (s(0), s(1), ..., s(n)) such that every s(i) is an integer, s(0) = 0, |s(i) - s(i-1)| = 1 for i = 1,2; |s(i) - s(i-1)| <= 1 for i >= 3, s(n) = 3. Also a(n) = T(n,n-3), where T is the array defined in A024996. 3
1, 2, 8, 24, 76, 232, 707, 2136, 6429, 19282, 57695, 172316, 513955, 1531362, 4559271, 13566288, 40349619, 119972214, 356634978, 1059985776, 3150165270, 9361450868, 27819215185, 82670528056, 245680350995, 730149455646, 2170105711452 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,2

LINKS

Table of n, a(n) for n=3..29.

FORMULA

Conjecture: (n+3)*a(n) +(-5*n-6)*a(n-1) +(3*n-11)*a(n-2) +(11*n-8)*a(n-3) +2*(-2*n+17)*a(n-4) +6*(-n+6)*a(n-5)=0. - R. J. Mathar, Jun 23 2013

CROSSREFS

First differences of A025181. Second differences of A014532.

Sequence in context: A231200 A066973 A130495 * A093833 A228404 A006952

Adjacent sequences:  A026067 A026068 A026069 * A026071 A026072 A026073

KEYWORD

nonn

AUTHOR

Clark Kimberling

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 14 05:51 EDT 2021. Contains 345018 sequences. (Running on oeis4.)