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A050189
T(n,4), array T as in A050186; a count of aperiodic binary words.
0
0, 5, 12, 35, 64, 126, 200, 330, 480, 715, 980, 1365, 1792, 2380, 3024, 3876, 4800, 5985, 7260, 8855, 10560, 12650, 14872, 17550, 20384, 23751, 27300, 31465, 35840, 40920, 46240, 52360, 58752, 66045, 73644, 82251, 91200
OFFSET
4,2
FORMULA
Seems to be n * A006918.
From Chai Wah Wu, Jun 11 2016: (Start)
a(n) = 2*a(n-1) + 2*a(n-2) - 6*a(n-3) + 6*a(n-5) - 2*a(n-6) - 2*a(n-7) + a(n-8) for n > 11 (conjectured).
G.f.: x^5*(5 + 2*x + x^2)/((1 - x)^5*(1 + x)^3) (conjectured). (End)
CROSSREFS
Sequence in context: A292104 A136113 A298992 * A308344 A116995 A032281
KEYWORD
nonn
STATUS
approved