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Search: id:A131190
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| A131190 |
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Numbers n such that the sequence {d(n) = (n^1 + 1) (n^2 + 2) ... (n^25 + 25) / 25! : n >= 0 } takes nonintegral values. |
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+0
1
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| 2, 7, 12, 18, 22, 27, 29, 37, 40, 47, 51, 52, 62, 72, 73, 77, 84, 87, 95, 97
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OFFSET
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1,1
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COMMENT
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Comment from the author: initial terms were calculated by Peter J.C. Moses; see comment in A129995. Comment from Max Alekseyev: 25! = 2^22 * 3^10 * 5^6 * 7^3 * 11^2 * 13 * 17 * 19 * 23 There is no divisibility for 5^6 and n in { 50m+2, 50m+12, 50m+22, 50m+27, 50m+37, 50m+47 } and for 11^2 and n in {11m+7} \ {121m+117}. Therefore a(n) is nonintegral for n in {50m+2} U {50m+12} U {50m+22} U {50m+27} U {50m+37} U {50m+47} U ( {11m+7} \ {121m+117} ).
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CROSSREFS
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Sequence in context: A105501 A016873 A019592 this_sequence A099353 A133459 A023669
Adjacent sequences: A131187 A131188 A131189 this_sequence A131191 A131192 A131193
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KEYWORD
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nonn
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AUTHOR
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Alexander R. Povolotsky (pevnev(AT)juno.com), Sep 25 2007
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