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A176168 Length of shortest series s(1..a(n))>0, with s(1)=1 and |s(i+1)-s(i)|=i and no value s(i) repeated, containing all the values 1..n 2
1, 2, 5, 5, 13, 17, 17, 20, 29, 36, 37, 37, 37, 37, 41, 45, 45, 56, 56, 58, 58, 58, 62, 62, 62, 62, 77, 77, 81, 81, 88, 89, 89, 89, 89, 89, 89, 89, 89, 89, 106, 106, 107, 107, 109, 113, 120, 121, 125, 125, 125, 125, 128, 128, 128, 132, 132, 132, 132, 144, 145, 148, 148, 148 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A series of finite versions of an infinite problem suggested on the Sequence Fans Mailing List

LINKS

R. H. Hardin, Table of n, a(n) for n=1..80

R. H. Hardin, Shortest series s(1..a(n)), n=1..80

EXAMPLE

a(5)=13 because the shortest series s() containing 1..5 is: 1 2 4 7 3 8 14 21 29 38 28 17 5

CROSSREFS

For encoded series see A176169

Sequence in context: A100953 A112835 A206625 * A308770 A222114 A308845

Adjacent sequences:  A176165 A176166 A176167 * A176169 A176170 A176171

KEYWORD

nonn

AUTHOR

R. H. Hardin Apr 10 2010

STATUS

approved

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Last modified December 9 13:50 EST 2019. Contains 329877 sequences. (Running on oeis4.)