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A180095
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a(n) = smallest number k such that three consecutive prime numbers prime(n), prime(n+1) and prime(n+2) are divisors of k, k+1 and k+2 respectively.
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4
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8, 54, 20, 791, 1936, 169, 4046, 114, 9453, 31929, 23901, 2664, 44977, 65188, 122482, 134991, 170982, 220027, 101103, 85555, 27886, 296724, 629140, 154326, 546207, 46864, 950587, 1043892, 1548890, 70738, 702945, 2389964
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(20) = 85555 is a term because prime(20) = 71 => 85555 = 71*1205 ; 85556 =
73*1172 and 85557 = 79*1083 where 71, 73 and 79 are three consecutive primes.
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MAPLE
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with(numtheory):for p from 1 to 50 do: p1:=ithprime(p):p2:=ithprime(p+1):p3:=ithprime(p+2):it:=0:for n from 1 to 5000000 while(it=0) do:if irem(n, p1)=0 and irem(n+1, p2)=0 and irem(n+2, p3)=0 then it:=1:printf(`%d, `, n):else fi:od:od:
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MATHEMATICA
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snk[n_]:=Module[{k=1}, While[!AllTrue[{k, k+1, k+2}/n, IntegerQ], k++]; k]; snk/@Partition[Prime[Range[35]], 3, 1] (* Harvey P. Dale, Feb 26 2015 *)
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PROG
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(Sage) def A180095(n): return crt([-2..0][::-1], [nth_prime(i) for i in [n..n+2]]) # D. S. McNeil, Jan 16 2011
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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