A045697 - OEIS

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A045697

Number of ternary words of length n (beginning 0) with autocorrelation function 2^(n-1)+3.

0, 0, 1, 0, 2, 8, 24, 70, 214, 638, 1930, 5782, 17394, 52160, 156620, 469786, 1409786, 4229148, 12688720, 38065506, 114200378, 342599212, 1027809200, 3083421770, 9250300098, 27750882922, 83252753086, 249758206958, 749274934114, 2247824645796, 6743474876960

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,5

LINKS

Table of n, a(n) for n=1..31.

FORMULA

a(2*n) = 3*a(2*n-1) + 2*a(n) - a(n+1) for n>=3; a(2*n-1) = 3*a(2*n-2) + 2*a(n) for n>=3.

CROSSREFS

Sequence in context: A293006 A018045 A050242 * A131569 A363602 A290904

Adjacent sequences: A045694 A045695 A045696 * A045698 A045699 A045700

KEYWORD

nonn

AUTHOR

TORSTEN.SILLKE(AT)LHSYSTEMS.COM

EXTENSIONS

More terms from Sean A. Irvine, Mar 18 2021

STATUS

approved