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Sum of two powers of 11.
5

%I #29 Jul 28 2021 04:29:33

%S 2,12,22,122,132,242,1332,1342,1452,2662,14642,14652,14762,15972,

%T 29282,161052,161062,161172,162382,175692,322102,1771562,1771572,

%U 1771682,1772892,1786202,1932612,3543122,19487172,19487182,19487292,19488502,19501812,19648222,21258732,38974342

%N Sum of two powers of 11.

%H T. D. Noe, <a href="/A073211/b073211.txt">Rows n = 0..100 of triangle, flattened</a>

%F T(n,m) = 11^n + 11^m, n = 0, 1, 2, 3, ..., m = 0, 1, 2, 3, ... n.

%F Bivariate g.f.: (2 - 12*x)/((1 - x)*(1 - 11*x)*(1 - 11*x*y)). - _J. Douglas Morrison_, Jul 26 2021

%e T(2,0) = 11^2 + 11^0 = 122.

%e Table T(n,m) begins:

%e 2;

%e 12, 22;

%e 122, 132, 242;

%e 1332, 1342, 1452, 2662;

%e 14642, 14652, 14762, 15972, 29282;

%e ...

%t t = 11^Range[0, 9]; Select[Union[Flatten[Table[i + j, {i, t}, {j, t}]]], # <= t[[-1]] + 1 &] (* _T. D. Noe_, Oct 09 2011 *)

%Y Cf. A001020 (powers of 11).

%Y Equals twice A073219.

%Y Sums of two powers of n: A073423 (0), A007395 (1), A173786 (2), A055235 (3), A055236 (4), A055237 (5), A055257 (6), A055258 (7), A055259 (8), A055260 (9), A052216 (10), A194887 (12), A072390 (13), A055261 (16), A073213 (17), A073214 (19), A073215 (23).

%K easy,nonn,tabl

%O 0,1

%A _Jeremy Gardiner_, Jul 20 2002