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A116656
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Slowest growing sequence of semiprimes having the semiprime-pairwise-sum property: for any i<j, a(i)+a(j) is semiprime.
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3
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4, 6, 51, 115, 511, 5263, 116623, 204091, 823363, 1144363, 78325123, 883337023, 6860264683, 19613836423, 167589841663
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OFFSET
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1,1
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LINKS
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Table of n, a(n) for n=1..15.
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EXAMPLE
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Resulting semiprimes are:
{10,55,119,515,5267,116627},
{57,121,517,5269,116629},
{166,562,5314,116674},
{626,5378,116738},
{5774,117134},
{121886}.
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MATHEMATICA
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spQ[n_] := Plus @@ Last /@ FactorInteger[n] == 2; L = {0, 4}; Do[n = L[[-1]] + 1; While[! AllTrue[n + L, spQ], n++]; AppendTo[L, n], {9}]; Rest@ L (* Giovanni Resta, Jun 13 2018 *)
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CROSSREFS
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Cf. A001358, A164979, A181620.
Sequence in context: A330978 A183369 A241159 * A012933 A013164 A013024
Adjacent sequences: A116653 A116654 A116655 * A116657 A116658 A116659
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KEYWORD
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more,nonn
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AUTHOR
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Zak Seidov, Feb 21 2006
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EXTENSIONS
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Three more terms from R. J. Mathar, Jan 23 2008
a(11)-a(12) from Donovan Johnson, Nov 11 2008
a(13) from Donovan Johnson, Jul 22 2011
a(14) from Giovanni Resta, Jun 13 2018
a(15) from Giovanni Resta, Jun 14 2018
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STATUS
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approved
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