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%I #5 Mar 31 2012 12:36:15
%S 2,12,22,49,54,110,91,179,154,238,190,360,215,376,333,453,290,604,334,
%T 607,478,634,411,904,428,771,658,882,504,1132,537,1023,832,1023,627,
%U 1453,625,1158,1007,1336,710,1614,753,1459,1191,1398,825,2016,831,1574,1337
%N Number of nondecreasing arrangements of 7 numbers in 0..n with the last equal to n and each after the second equal to the sum of one or two of the preceding four
%C Row 5 of A189326
%H R. H. Hardin, <a href="/A189330/b189330.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = -4*a(n-1) -13*a(n-2) -33*a(n-3) -76*a(n-4) -156*a(n-5) -300*a(n-6) -538*a(n-7) -919*a(n-8) -1494*a(n-9) -2337*a(n-10) -3518*a(n-11) -5129*a(n-12) -7245*a(n-13) -9954*a(n-14) -13307*a(n-15) -17352*a(n-16) -22075*a(n-17) -27440*a(n-18) -33327*a(n-19) -39579*a(n-20) -45945*a(n-21) -52136*a(n-22) -57780*a(n-23) -62486*a(n-24) -65817*a(n-25) -67357*a(n-26) -66703*a(n-27) -63526*a(n-28) -57579*a(n-29) -48739*a(n-30) -37025*a(n-31) -22608*a(n-32) -5832*a(n-33) +12817*a(n-34) +32691*a(n-35) +53055*a(n-36) +73066*a(n-37) +91885*a(n-38) +108650*a(n-39) +122610*a(n-40) +133081*a(n-41) +139585*a(n-42) +141780*a(n-43) +139585*a(n-44) +133081*a(n-45) +122610*a(n-46) +108650*a(n-47) +91885*a(n-48) +73066*a(n-49) +53055*a(n-50) +32691*a(n-51) +12817*a(n-52) -5832*a(n-53) -22608*a(n-54) -37025*a(n-55) -48739*a(n-56) -57579*a(n-57) -63526*a(n-58) -66703*a(n-59) -67357*a(n-60) -65817*a(n-61) -62486*a(n-62) -57780*a(n-63) -52136*a(n-64) -45945*a(n-65) -39579*a(n-66) -33327*a(n-67) -27440*a(n-68) -22075*a(n-69) -17352*a(n-70) -13307*a(n-71) -9954*a(n-72) -7245*a(n-73) -5129*a(n-74) -3518*a(n-75) -2337*a(n-76) -1494*a(n-77) -919*a(n-78) -538*a(n-79) -300*a(n-80) -156*a(n-81) -76*a(n-82) -33*a(n-83) -13*a(n-84) -4*a(n-85) -a(n-86)
%e Some solutions for n=3
%e ..2....0....1....1....1....3....0....1....1....0....0....1....1....1....1....1
%e ..3....3....1....1....1....3....1....1....1....1....1....2....1....2....2....1
%e ..3....3....2....1....1....3....1....1....1....1....1....2....1....3....2....2
%e ..3....3....2....1....2....3....2....2....2....2....1....3....1....3....2....2
%e ..3....3....2....1....2....3....2....3....2....3....2....3....2....3....3....3
%e ..3....3....3....2....2....3....2....3....3....3....3....3....3....3....3....3
%e ..3....3....3....3....3....3....3....3....3....3....3....3....3....3....3....3
%K nonn
%O 1,1
%A _R. H. Hardin_ Apr 20 2011
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