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A189893 Recurrence sequence derived from the digits of the square root of 5 after its decimal point. 3
0, 4, 10, 65, 173, 22, 96, 15, 48, 78, 13, 201, 487, 594, 2719, 5146, 8719, 11530, 15308, 76411, 76016, 42220, 67129, 45349, 170266, 255576, 457846, 865810, 1131083, 8045547, 7669757 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..30.

FORMULA

a(0) = 0; for i >= 0, a(i+1) = position of first occurrence of a(i) in decimal places of sqrt(5).

EXAMPLE

sqrt(5) = 2.2360679774997896964091736687...

So for example, with a(0) = 0, a(1) = 4 because the 4th digit after the decimal point is 0; a(2) = 10 because the 10th digit after the decimal point is 4 and so on.

MAPLE

with(StringTools): Digits:=10000: G:=convert(evalf(sqrt(5)), string): a[0]:=0: for n from 1 to 17 do a[n]:=Search(convert(a[n-1], string), G)-2:printf("%d, ", a[n-1]):od:

CROSSREFS

Other recurrence sequences: A097614 for Pi, A098266 for e, A098289 for log(2), A098290 for Zeta(3), A098319 for 1/Pi, A098320 for 1/e, A098321 for gamma, A098322 for G, A098323 for 1/G, A098324 for Golden Ratio (phi), A098325 for sqrt(Pi), A098326 for sqrt(2), A120482 for sqrt(3), A098327 for sqrt(e), A098328 for 2^(1/3).

Sequence in context: A203226 A300642 A146304 * A197939 A207160 A244297

Adjacent sequences:  A189890 A189891 A189892 * A189894 A189895 A189896

KEYWORD

base,nonn,more

AUTHOR

Nathaniel Johnston, Apr 30 2011

STATUS

approved

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Last modified December 17 09:23 EST 2018. Contains 318193 sequences. (Running on oeis4.)