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A119783
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Numerator of Sum[ i^3/(n-i+1), {i,1,n}].
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0
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1, 17, 94, 965, 841, 6167, 18044, 225489, 75220, 4280111, 899494, 86645897, 26288822, 41914055, 296912584, 5893703327, 1703822073, 49486578079, 14076109870, 12725008135, 1190932611, 122366761563, 203957791852
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| Prime p divides a(2p-1), p>3. Prime p divides a(3p-1), p>2. Prime p divides a(p-1), p>3. p^2 divides a(p^2-1) for prime p>3. p^3 divides a(p^3-1) for prime p>3. p^4 divides a(p^4-1) for prime p>3. p^5 divides a(p^5-1) for p>3.
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FORMULA
| a(n) = numerator[ Sum[ i^3/(n-i+1), {i,1,n}]].
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MATHEMATICA
| Numerator[Table[Sum[i^3/(n-i+1), {i, 1, n}], {n, 1, 50}]]
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CROSSREFS
| Cf. A007406, A001008, A027612.
Sequence in context: A159676 A061971 A061222 * A199042 A094407 A070186
Adjacent sequences: A119780 A119781 A119782 * A119784 A119785 A119786
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KEYWORD
| frac,nonn
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AUTHOR
| Alexander Adamchuk (alex(AT)kolmogorov.com), Jun 25 2006
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