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A181737
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Partial products of A181103.
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3
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2, 6, 42, 546, 9282, 176358, 4056234, 117630786, 4822862226, 226674524622, 13373796952698, 1110025147073934, 98792238089580126, 9978016047047592726, 1067647717034092421682, 146267737233670661770434
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OFFSET
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1,1
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COMMENTS
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a(n+1)-a(n) is divisible by 6 for n > 1.
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LINKS
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EXAMPLE
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First three terms of A181103 are 2, 3, 7, so a(3) = 2*3*7 = 42.
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PROG
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(Magma) A181103:=function(n); S:=[2, 3]; if n le 2 then return S[n]; end if; p:=5; for k in [3..n] do while not IsPrime(Abs(S[k-2]+S[k-1]-p)) do p:=NextPrime(p); end while; Append(~S, p); if k eq n then return p; end if; p:=NextPrime(p); end for; end function; A181737:=function(n); S:=[ A181103(k): k in [1..n] ]; T:=[ m eq 1 select S[1] else Self(m-1)*S[m]: m in [1..n] ]; return T[n]; end function; [ A181737(n): n in [1..20] ]; // Klaus Brockhaus, Dec 19 2010
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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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