The OEIS is supported by the many generous donors to the OEIS Foundation.

 Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 60th year, we have over 367,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”). Other ways to Give
 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A228256 Number of third differences of arrays of length n+3 of numbers in 0..4. 1
 33, 565, 6419, 53315, 315601, 1688101, 8717049, 44633821, 227363409, 1153594261, 5835080169, 29443836301, 148292923329, 745759583941, 3745977788889, 18798608421181, 94267920012849, 472439111692021, 2366593604971209 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS R. H. Hardin, Table of n, a(n) for n = 1..121 FORMULA Empirical: a(n) = 9*a(n-1) - 20*a(n-2) for n>8. Conjectures from Colin Barker, Sep 10 2018: (Start) G.f.: x*(33 + 268*x + 1994*x^2 + 6844*x^3 - 35854*x^4 - 86008*x^5 - 163840*x^6 - 57600*x^7) / ((1 - 4*x)*(1 - 5*x)). a(n) = 5^(3+n) - 4^(3+n) for n>6. (End) EXAMPLE Some solutions for n=4: .12..-10....2...-7....8...-5....2..-13...-7..-15...-6...-3....5....3....7....2 .-7....8....3....6...-2....1....0...13....4....9....0....4...-2...-3..-12....3 .-1...-6....1....1...-1...-3...-7..-12....1....0....9...-1...-6....2...12...-1 ..4....8...-7...-1...-4...-2...10...12...-6...-2..-13...-3...10...-5...-6....5 CROSSREFS Column 4 of A228260. Sequence in context: A188357 A126923 A010985 * A197361 A282926 A172362 Adjacent sequences: A228253 A228254 A228255 * A228257 A228258 A228259 KEYWORD nonn AUTHOR R. H. Hardin, Aug 19 2013 STATUS approved

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

Last modified December 4 01:51 EST 2023. Contains 367541 sequences. (Running on oeis4.)