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A134631
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a(n) = 5*n^5 - 3*n^3 + 2*n^2. Coefficients and exponents are the prime numbers in decreasing order.
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2
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0, 4, 144, 1152, 4960, 15300, 38304, 83104, 162432, 293220, 497200, 801504, 1239264, 1850212, 2681280, 3787200, 5231104, 7085124, 9430992, 12360640, 15976800, 20393604, 25737184, 32146272, 39772800, 48782500, 59355504, 71686944, 85987552, 102484260, 121420800, 143058304, 167675904, 195571332, 227061520
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OFFSET
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0,2
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LINKS
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FORMULA
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a(n) = 5*n^5 - 3*n^3 + 2*n^2.
G.f.: 4x*(1+30x+87x^2+32x^3)/(1-x)^6. - R. J. Mathar, Nov 14 2007
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EXAMPLE
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a(4)=4960 because 4^5=1024, 5*1024=5120, 4^3=64, 3*64=192, 4^2=16, 2*16=32 and we can write 5120 - 192 + 32 = 4960.
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MATHEMATICA
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Table[5n^5-3n^3+2n^2, {n, 0, 40}] (* or *) LinearRecurrence[{6, -15, 20, -15, 6, -1}, {0, 4, 144, 1152, 4960, 15300}, 40] (* Harvey P. Dale, Jan 20 2023 *)
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PROG
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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