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%I #27 Apr 09 2023 08:06:46
%S 4,0,19,5,11,22,1,10,3,7,231,34,121,55,254,366,0,35,2,188,19,54,62,
%T 131,78,213,67,63,51,174,40,137,181,5,26,56,28,98,32,6,105,90,347,27,
%U 58,21,70,102,15,11,214,394,66,111,57,768,30,48,22,166,68,1,50
%N The location of the first occurrence of n in the decimal expansion of phi (the golden ratio, 1.6180339887...).
%C Locations in the expansion of phi are numbered 0 for the digit before the decimal point, 1 for the first digit after the decimal point, and so on.
%F a(n) = A088577(n) - 1.
%e The first occurrence of 0 in phi occurs 4 places after the decimal point, so a(0)=4; 5 first occurs 22 places after the decimal point, so a(5)=22; 10 first occurs 231 places after the decimal point so a(10)=231.
%t Table[-1 + SequencePosition[#, IntegerDigits@ n][[1, 1]], {n, 0, 50}] &@ First@ RealDigits@ N[GoldenRatio, 10^4]
%Y Cf. A001622 (phi)
%Y Cf. A088577 (1-based locations).
%Y Cf. A078197 (for e), A176341 (for Pi), A014777 (for Pi but different indexing).
%K nonn,base
%O 0,1
%A _James C. McMahon_, Apr 06 2023