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A108663 In the decimal expansion of Pi, lengths of sublists with alternative parity. 2
2, 1, 3, 2, 3, 1, 4, 1, 1, 6, 2, 1, 1, 1, 3, 5, 4, 1, 8, 1, 1, 3, 2, 1, 1, 2, 2, 1, 1, 1, 1, 1, 1, 10, 2, 5, 1, 3, 2, 2, 3, 2, 2, 2, 1, 5, 3, 3, 1, 4, 1, 1, 2, 5, 3, 1, 1, 3, 3, 1, 4, 3, 1, 4, 4, 1, 1, 4, 1, 2, 1, 1, 3, 1, 1, 1, 2, 1, 4, 6, 1, 2, 2, 1, 2, 1, 1, 1, 2, 6, 1, 1, 3, 2, 4, 3, 1, 3, 2, 4, 3, 2, 1, 1, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Take the decimal expansion of Pi: s={3,1,4,1,5,9,2,6,5,3,5,8,9,7,9,3,2,3,8,4,6,2,6,4,3,3,8,3,2,7,9,5,0,2,8,8,4,1,9}. Split s into sublists each with digits of the same parity:{{3,1},{4},{1,5,9},{2,6},{5,3,5},{8},{9,7,9,3},{2},{3},{8,4,6,2,6,4},{3,3},{8},{3}}. The sequence gives the lengths of the sublists: 2,1,3,2,3,1,4,1,1,6,2,1,1,1,3,5,4,1,8.

LINKS

Table of n, a(n) for n=1..105.

MATHEMATICA

A108663=Length/@Split[RealDigits[N[Pi, 300]][[1]], Mod[ #1-#2, 2]==0&]

CROSSREFS

Sequence in context: A151682 A159918 A278573 * A057940 A097285 A057432

Adjacent sequences:  A108660 A108661 A108662 * A108664 A108665 A108666

KEYWORD

base,nonn

AUTHOR

Zak Seidov, Jun 17 2005

STATUS

approved

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Last modified December 10 17:28 EST 2016. Contains 279005 sequences.