0,2

Note that the first six terms are Fibonacci numbers.

M. Aigner, Moving into the desert with Fibonacci, Mathematics Magazine, 70 (1997), 11-21.

E. R. Berlekamp, J. H. Conway and R. K. Guy, Winning Ways, Academic Press, NY, 2 vols., 1982, see p. 715.

N. Eriksen, H. Eriksson and K. Eriksson, Diagonal checker-jumping and Eulerian numbers for colorsigned permutations, Electron. J. Combin., 7 (2000), #R3.

G. I. Bell, The peg solitaire army.

G. I. Bell, D. S. Hirschberg and P. Guerrero-Garcia, The minimum size required of a solitaire army.

Eric Weisstein's World of Mathematics, Conway's Soldiers.

It is easy to show that a(n) >= a(n-1)+a(n-2). However, finding the last 3 terms in this sequence is not easy.

a(1)=2 because it takes 2 men to go one step or level forward.

Cf. A014225, A014227.

Sequence in context: A018067 A068202 A096796 this_sequence A074030 A024318 A132915

Adjacent sequences: A125727 A125728 A125729 this_sequence A125731 A125732 A125733

fini,full,nonn

George I. Bell (gibell(AT)comcast.net), Feb 02 2007