0,1

a(n)^2 - 8*b(n)^2 = 17, with the companion sequence b(n)= A077241(n).

Index entries for sequences related to Chebyshev polynomials.

a(2*k)= A077240(k) and a(2*k+1)= A077239(k), k>=0.

G.f.: (1-x)*(5+12*x+5*x^2)/(1-6*x^2+x^4).

23 = a(2) = sqrt(8*A077241(2)^2 + 17) = sqrt(8*8^2 + 17)= sqrt(529) = 23.

Adjacent sequences: A077239 A077240 A077241 this_sequence A077243 A077244 A077245

Sequence in context: A028281 A105890 A018656 this_sequence A121182 A028287 A121605

nonn,easy

Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de), Nov 08 2002