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A075411
Squares of A002276.
9
0, 4, 484, 49284, 4937284, 493817284, 49382617284, 4938270617284, 493827150617284, 49382715950617284, 4938271603950617284, 493827160483950617284, 49382716049283950617284, 4938271604937283950617284, 493827160493817283950617284, 49382716049382617283950617284
OFFSET
0,2
COMMENTS
A transformation of the Wonderful Demlo numbers (A002477).
FORMULA
a(n) = A002276(n)^2 = (2 * A002275(n) )^2 = 4 * (A002275(n) )^2.
From Chai Wah Wu, Apr 24 2017: (Start)
a(n) = 111*a(n-1) - 1110*a(n-2) + 1000*a(n-3) for n > 2.
G.f.: 4*x*(1 + 10*x)/((1 - x)*(1 - 10*x)*(1 - 100*x)).
(End)
a(n) = 4*(10^n - 1)^2/81. - Colin Barker, Apr 25 2017
EXAMPLE
a(2) = 22^2 = 484.
MATHEMATICA
LinearRecurrence[{111, -1110, 1000}, {0, 4, 484}, 30] (* Vincenzo Librandi, Apr 25 2017 *)
PROG
(Magma) I:=[0, 4, 484]; [n le 3 select I[n] else 111*Self(n-1)-1110*Self(n-2)+1000*Self(n-3): n in [1..20]]; // Vincenzo Librandi, Apr 25 2017
KEYWORD
easy,nonn
AUTHOR
Michael Taylor (michael.taylor(AT)vf.vodafone.co.uk), Sep 14 2002
STATUS
approved