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A261726
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a(n) = binomial(prime(n+1)-1, prime(n)-1).
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1
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2, 6, 15, 210, 66, 1820, 153, 7315, 376740, 435, 1947792, 91390, 861, 163185, 20358520, 40475358, 1770, 90858768, 916895, 2556, 256851595, 1749060, 541931236, 132601016340, 3921225, 5151, 4967690, 5778, 6210820, 1378095785451705375, 11358880, 7858539612
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OFFSET
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1,1
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LINKS
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FORMULA
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a(n) = binomial(prime(n+1)-1, prime(n)-1).
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EXAMPLE
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For n = 2, a(n) = binomial(prime(n+1)-1, prime(n)-1) = binomial(4,2) = 6.
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MATHEMATICA
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Binomial[#[[2]]-1, #[[1]]-1]&/@Partition[Prime[Range[40]], 2, 1] (* Harvey P. Dale, Apr 01 2021 *)
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PROG
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(PARI) a(n) = binomial(prime(n+1)-1, prime(n)-1);
vector(35, n, a(n))
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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