A098808 a(n) = 2^(n + 11) - 11.

2037, 4085, 8181, 16373, 32757, 65525, 131061, 262133, 524277, 1048565, 2097141, 4194293, 8388597, 16777205, 33554421, 67108853, 134217717, 268435445, 536870901, 1073741813, 2147483637, 4294967285, 8589934581, 17179869173

Offset: 0

Author

Parthasarathy Nambi, Oct 06 2004

Keywords

• nonn
• easy

Examples

			a(0) = 2^11 - 11 = 2037.
a(1) = 2^12 - 11 = 4085.
		

Links

• T. Skolem, S. Chowla and D. J. Lewis, The diophantine equation 2^(n+2) - 7 = x^2 and related problems, Proc. Amer. Math. Soc., 10 (1959), 663-669.
• Index entries for linear recurrences with constant coefficients, signature (3,-2).

Crossrefs

Cf. A038198, A060728.

Programs

Mathematica

Table[2^(n + 11) - 11, {n, 0, 30}] (* Stefan Steinerberger, Mar 06 2006 *)

PARI

first(m)=vector(m,i,i--;2^(i + 11) - 11) \\ Anders Hellström, Aug 26 2015

Formula

From Colin Barker, May 11 2012: (Start)

a(n) = 3*a(n-1)-2*a(n-2).

G.f.: (2037-2026*x)/((1-x)*(1-2*x)). (End)

Extensions

More terms from Stefan Steinerberger, Mar 06 2006