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 A103186 a(n) is the position of the start of the first occurrence of n > a(n-1) after the decimal point in Pi = 3.14159265358979323846264338327950288... 4
 1, 6, 9, 19, 31, 41, 47, 52, 55, 163, 174, 220, 281, 295, 314, 396, 428, 446, 495, 600, 650, 661, 698, 803, 822, 841, 977, 1090, 1124, 1358, 1435, 1501, 1667, 1668, 1719, 1828, 1926, 1968, 1987, 2007, 2161, 2210, 2236, 2261, 2305, 2416, 2509, 2555, 2595 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The digits at position 1667 are "334", so according to the strict definition of this sequence, a(33) is 1667 and a(34) is 1668. However, this would not enable a person to mark in bold-face the counting numbers within the digits of pi, which was the inspiration for this sequence. Surprisingly, if overlapping is not allowed, this changes only one element of the sequence. a(34) becomes 1700 and a(35) remains 1719. No other overlapping occurs within the first 100,000 decimal digits of Pi. - Graeme McRae, Mar 20 2005 LINKS Robert G. Wilson v, Table of n, a(n) for n = 1..9999 Dave Andersen, The Pi-Search Page. Bob Happelberg, Bob's Poetry Page for Feb 2005 EXAMPLE Moving always to the right in the decimal expansion of Pi, the string "1" is found at position 1 counting from the first digit after the decimal point, the string "2" is found at position 6, the string "3" at position 6, the string "4" at position 19, etc. MATHEMATICA p = ToString[ FromDigits[ RealDigits[ N[Pi - 3, 2600]][[1]]]]; lst = {0}; Do[a = StringPosition[p, ToString[n], 1][[1, 1]]; AppendTo[lst, a + lst[[ -1]]]; p = StringDrop[p, a], {n, 49}]; Rest[lst] (* Robert G. Wilson v, Mar 19 2005 *) PROG (MAGMA) k := 3000; R := RealField(k); S := IntegerToString(Round(10^k*(-3 + Pi(R)))); Q := []; d := 0; for n in [1..49] do p:= Position(S, IntegerToString(n)); d+:=p; Append(~Q, d); S := Substring(S, p+1, #S-p); end for; Q; /* Klaus Brockhaus, Feb 15 2007 */ (PARI) lista(nn, t=10^5) = {default(realprecision, t); my(d, k, v=digits(floor(Pi*10^t))); for(n=1, nn, d=digits(n); until(v[k+1..k+#d]==d, k++); print1(k, ", ")); } \\ Jinyuan Wang, Feb 18 2021 CROSSREFS Cf. A000796, A078197, A014777 (another version). Sequence in context: A265099 A023041 A118277 * A011988 A161782 A154783 Adjacent sequences:  A103183 A103184 A103185 * A103187 A103188 A103189 KEYWORD nonn,base,easy AUTHOR Suggested by Bob's Poetry Page. - Alonso del Arte, Mar 01 2005 EXTENSIONS More terms from Graeme McRae and Robert G. Wilson v, Mar 19 2005 STATUS approved

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Last modified November 30 21:20 EST 2021. Contains 349426 sequences. (Running on oeis4.)