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A166941
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Product plus sum of four consecutive nonnegative numbers.
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6
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6, 34, 134, 378, 862, 1706, 3054, 5074, 7958, 11922, 17206, 24074, 32814, 43738, 57182, 73506, 93094, 116354, 143718, 175642, 212606, 255114, 303694, 358898, 421302, 491506, 570134, 657834, 755278, 863162, 982206, 1113154, 1256774
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OFFSET
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0,1
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COMMENTS
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a(n) = (n*...*(n+3))+(n+...+(n+3)), n >= 0.
All terms are even.
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LINKS
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FORMULA
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a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) + 24 for n > 3; a(0)=6, a(1)=34, a(2)=134, a(3)=378. - Klaus Brockhaus, Nov 14 2009
G.f.: 2*(3 + 2*x + 12*x^2 - 6*x^3 + x^4)/(1-x)^5. - Klaus Brockhaus, Nov 14 2009
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EXAMPLE
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a(0) = 0*1*2*3+0+1+2+3 = 0+6 = 6.
a(1) = 1*2*3*4+1+2+3+4 = 24+10 = 34.
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MATHEMATICA
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lst={}; Do[p=(n+3)*(n+2)*(n+1)*n+(n+3)+(n+2)+(n+1)+n; AppendTo[lst, p], {n, 0, 5!}]; lst
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PROG
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(Magma) [ &*s + &+s where s is [n..n+3]: n in [0..32] ]; // Klaus Brockhaus, Nov 14 2009
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CROSSREFS
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Cf. A001477 (nonnegative integers), A167858 (3,14,36,36,12,0,0,0,...), A028387 (n+(n+1)^2), A167875, A166942, A166943.
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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