

A108664


In the decimal expansion of Pi, lengths of sublists ending with 9.


1



6, 7, 2, 16, 8, 4, 2, 1, 10, 3, 4, 17, 1, 20, 22, 7, 15, 25, 11, 7, 3, 3, 6, 9, 6, 33, 2, 10, 25, 10, 34, 3, 5, 5, 12, 3, 32, 3, 8, 15, 2, 2, 4, 11, 7, 19, 1, 5, 17, 5, 9, 2, 3, 26, 2, 4, 9, 7, 4, 11, 8, 22, 42, 3, 19, 6, 11, 11, 4, 3, 4, 8, 1, 8, 4, 14, 6, 9, 1, 14, 1, 1, 1, 1, 1, 5, 5, 1, 5, 11
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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}. Split s into sublists each ending with 9: {{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}}. The sequence gives the lengths of the sublists: 6,7,2,16,8,4,2,1,10,3,4,17,1,20,22,7. Cf. A053753 (positions of 9's in the decimal expansion of Pi).


LINKS

Table of n, a(n) for n=1..90.


FORMULA

a(n) = A053753(n+1)  A053753(n).


CROSSREFS

Cf. A000796, A037007, A053753, A108663, A139727, A014974.
Sequence in context: A316165 A267251 A259526 * A160155 A277135 A153628
Adjacent sequences: A108661 A108662 A108663 * A108665 A108666 A108667


KEYWORD

base,nonn


AUTHOR

Zak Seidov, Jun 17 2005


STATUS

approved



