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 A295955 Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n) + 1, where a(0) = 3, a(1) = 4, b(0) = 1, b(1) = 2, b(2) = 5, and (a(n)) and (b(n)) are increasing complementary sequences. 2

%I

%S 3,4,13,24,45,78,133,222,367,602,984,1602,2603,4223,6845,11088,17954,

%T 29064,47041,76129,123196,199352,322576,521957,844563,1366551,2211146,

%U 3577730,5788910,9366675,15155621,24522333,39677992,64200364,103878396,168078801

%N Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n) + 1, where a(0) = 3, a(1) = 4, b(0) = 1, b(1) = 2, b(2) = 5, and (a(n)) and (b(n)) are increasing complementary sequences.

%C The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. a(n)/a(n-1) -> (1 + sqrt(5))/2 = golden ratio (A001622).

%C See A295862 for a guide to related sequences.

%H Clark Kimberling, <a href="/A295955/b295955.txt">Table of n, a(n) for n = 0..2000</a>

%H Clark Kimberling, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL10/Kimberling/kimberling26.html">Complementary equations</a>, J. Int. Seq. 19 (2007), 1-13.

%e a(0) = 3, a(1) = 4, b(0) = 1, b(1) = 2, b(2) = 5

%e b(3) = 6 (least "new number")

%e a(2) = a(1) + a(0) + b(2) + 1 = 13

%e Complement: (b(n)) = (1, 2, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, ...)

%t a = 3; a = 4; b = 1; b = 2; b = 5;

%t a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n] + 1;

%t j = 1; While[j < 6, k = a[j] - j - 1;

%t While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++];

%t Table[a[n], {n, 0, k}]; (* A295955 *)

%Y Cf. A001622, A000045, A295862.

%K nonn,easy

%O 0,1

%A _Clark Kimberling_, Dec 08 2017

%E Definition corrected by _Georg Fischer_, Sep 27 2020

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Last modified July 26 08:42 EDT 2021. Contains 346294 sequences. (Running on oeis4.)