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 A296491 Decimal expansion of ratio-sum for A294170; see Comments. 4

%I

%S 6,3,5,8,7,1,3,0,2,6,9,8,4,2,9,9,3,5,4,5,4,1,4,7,7,9,6,8,8,9,0,6,0,5,

%T 5,0,4,3,0,2,3,3,0,8,6,8,8,9,4,5,7,0,7,3,2,5,1,6,1,3,3,3,0,1,0,1,5,5,

%U 4,3,0,8,3,2,4,6,4,3,7,3,6,8,1,7,5,9

%N Decimal expansion of ratio-sum for A294170; see Comments.

%C Suppose that A = (a(n)), for n >= 0, is a sequence, and g is a real number such that a(n)/a(n-1) -> g. The ratio-sum for A is |a(1)/a(0) - g| + |a(2)/a(1) - g| + ..., assuming that this series converges. For A = A294170, we have g = (1 + sqrt(5))/2, the golden ratio (A001622). See the guide at A296469 for related sequences.

%e 6.358713026984299354541477968890605504302...

%t a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4; b[2] = 5;

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

%t j = 1; While[j < 16, k = a[j] - j - 1;

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

%t u = Table[a[n], {n, 0, k}]; (* A294170 *)

%t g = GoldenRatio; s = N[Sum[- g + a[n]/a[n - 1], {n, 1, 1000}], 200]

%t Take[RealDigits[s, 10][[1]], 100] (* A296491 *)

%Y Cf. A001622, A294170, A296284, A296492.

%K nonn,easy,cons

%O 1,1

%A _Clark Kimberling_, Dec 20 2017

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Last modified June 2 18:17 EDT 2020. Contains 334787 sequences. (Running on oeis4.)