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A238697
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Quotients connected with the Banach matchboxes problem: Sum_{i=1..prime(n)-7} 2^(i-1)*binomial(i+2,3)/prime(n) (case 3).
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9
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0, 19, 197, 10481, 64027, 1980327, 259179061, 1257208799, 131286703021, 2756321451033, 12473384091267, 250290955437775, 21588599628845597, 1792050990708087027, 7763319803561678613, 620323392829436218475, 11365013042482773469559, 48487140450183407727097
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OFFSET
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4,2
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COMMENTS
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LINKS
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MATHEMATICA
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Array[Sum[2^(i - 1)*Binomial[i + 2, 3]/#, {i, # - 7}] &@ Prime@ # &, 18, 4] (* Michael De Vlieger, Dec 06 2018 *)
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PROG
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(PARI) a(n) = sum(i=1, prime(n)-7, 2^(i-1)*binomial(i+2, 3))/prime(n); \\ Michel Marcus, Dec 06 2018
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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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