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%I #9 Feb 06 2019 02:00:47
%S 144,927,2872,6930,15109,31489,64256,129792,260864,523008,1047296,
%T 2095872,4193024,8387328,16775936,33553152,67107584,134216448,
%U 268434176,536869632,1073740544,2147482368,4294966016,8589933312,17179867904
%N If an array is made of columns of -nacci sequences, fibo-, tribo- etc. all starting w. 1,1,2 etc, the NW to SE diagonals can be extended by computation. The above is diagonal 11. See A159741 for details.
%F a(n) = 3*a(n-1) - 2*a(n-2), n > 8. - _R. J. Mathar_, Apr 22 2009
%F Interpolate a(n) = (4*n^5 - 60*n^4 + 415*n^3 - 1665*n^2 + 3826*n + 11745)/15 offset 0 and b(n) = -4*n^5 + 50*n^4 - 305*n^3 + 1127.5*n^2 - 2443.5 + 17430)/15 offset 0. Add the leading 144. Binomially transform. - Al Hakanson (hawkuu(AT)gmail.com), Jun 08 2009
%p T := proc(n,m) option remember ; if n < 0 then 0; elif n <= 1 then 1; elif n = 2 then 2; else add(procname(n-i,m),i=1..m) ; fi: end: A159748 := proc(n) T(n+10,n+1) ; end: seq(A159748(n),n=1..40) ; # _R. J. Mathar_, Apr 22 2009
%Y Cf. A159741 .
%K nonn
%O 1,1
%A Al Hakanson (hawkuu(AT)gmail.com), Apr 20 2009
%E More terms from _R. J. Mathar_, Apr 22 2009
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