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A107783
Array defined in A064643 read in direction in which it was created.
2
1, 1, 2, 1, 5, 6, 1, 13, 21, 22, 1, 45, 84, 104, 105, 1, 211, 412, 562, 630, 631, 1, 1263, 2500, 3558, 4285, 4602, 4603, 1, 9207, 18305, 26560, 33180, 37573, 39468, 39469, 1, 78939, 157243, 230496, 293794, 342944, 375058, 388869, 388870, 1, 777741
OFFSET
0,3
MAPLE
A107783 := proc(n, k) option remember ; if n < 0 or k < 0 or k > n then 0 ; elif n =0 then 1; elif n mod 2 = 1 then if n = k then 1; else A107783(n, k+1)+A107783(n-1, k-1)+A107783(n-1, k)+A107783(n-2, k-1) ; fi ; else if k = 0 then 1; else A107783(n, k-1)+A107783(n-1, k-1)+A107783(n-1, k)+A107783(n-2, k-1) ; fi ; fi ; end: for n from 0 to 11 do if ( n mod 2 ) = 1 then kstrt := n ; else kstrt := 0 ; fi ; kend := n-kstrt : for k from kstrt to kend by sign(kend-kstrt) do printf("%d, ", A107783(n, k)) ; od: od: # R. J. Mathar, Aug 13 2007
CROSSREFS
KEYWORD
nonn,tabl,easy
AUTHOR
N. J. A. Sloane, Jun 15 2005
EXTENSIONS
More terms from R. J. Mathar, Aug 13 2007
STATUS
approved