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A109865 Consider Pi = 3.1415926535897932384626433832795... On taking the absolute successive differences between successive digits ignoring the decimal point one gets the array shown in Comments (below). Sequence contains the first term of each row (the first diagonal). 1
3, 2, 1, 1, 0, 0, 2, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,1
COMMENTS
3...1...4...1...5...9...2...6...5...3...5...8...9...7...9...3...2...3...8...4
..2...3...3...4...4...7...4...1...2...2...3...1...2...2...6...1...1...5...4
....1...0...1...0...3...3...3...1...0...1...2...1...0...4...5...0...4...1
......1...1...1...3...0...0...2...1...1...1...1...1...4...1...5...4...3
........0...0...2...3...0...2...1...0...0...0...0...3...3...4...1...1
..........0...2...1...3...2...1...1...0...0...0...3...0...1...3...0
............2...1...2...1...1...0...1...0...0...3...3...1...2...3
Call this the Absolute Successive Difference function of an irrational number k denoted by ASDE(k). Then ASDE(Pi) = 3.211002110001... Subsidiary sequences: For e, phi, 2^(1/2), 3^(1/2), Euler's constant and other important irrational numbers can be included.
LINKS
MAPLE
Digits := 200: asde := proc(n, L) local b, L2, i, j; b := L ; for i from 1 to n do L2 := [] ; for j from 1 to nops(b)-1 do L2 := [op(L2), abs(op(j+1, b)-op(j, b))] ; od: b := L2 ; od: op(1, b) ; end: A109864 := proc(n) local piL, i ; piL := [] ; for i from 1 to n+1 do piL := [op(piL), floor(Pi*10^(i-1)) mod 10] ; od: asde(n, piL) ; end: seq( A109864(n), n=0..100) ; # R. J. Mathar, Feb 11 2008
MATHEMATICA
First[#]&/@Module[{nn=110, pi}, {pi=RealDigits[Pi, 10, nn][[1]]}; NestList[ Abs[ Differences[ #]]&, pi, nn-1]] (* Harvey P. Dale, Jun 14 2016 *)
CROSSREFS
Cf. A000796.
Sequence in context: A202820 A113081 A172184 * A206713 A096874 A090046
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Jul 09 2005
EXTENSIONS
More terms from R. J. Mathar, Feb 11 2008
Definition clarified by Harvey P. Dale, Jun 14 2016
STATUS
approved

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Last modified April 25 12:33 EDT 2024. Contains 371969 sequences. (Running on oeis4.)