A157616 - OEIS

A157616

On an n X n board, a(n) is the maximal number of squares covered by a self-avoiding path that starts from a corner and is made of alternated vertical and horizontal unitary steps.

1, 4, 6, 14, 18, 32, 38, 58, 66, 92, 102, 134

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OFFSET

1,2

COMMENTS

From an idea of Leroy Quet, discussed on the SeqFan mailing list.

David Wilson conjectures that the formula for a(n) is:

a(1)=1, then, a(n)=n^2-n+2 for n even, and a(n)=n^2-2n+3 for n>1 odd.

LINKS

Table of n, a(n) for n=1..12.

Giovanni Resta, Illustration of initial terms

CROSSREFS

A157615, A157617

Sequence in context: A310645 A310646 A310647 * A029647 A310648 A310649

Adjacent sequences: A157613 A157614 A157615 * A157617 A157618 A157619

KEYWORD

hard,more,nonn

AUTHOR

Giovanni Resta, Mar 03 2009

STATUS

approved