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Search: id:A075688
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| A075688 |
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Pair sums are even interprimes. |
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+0
2
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OFFSET
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1,1
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COMMENT
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In the sequence all pair sums are even interprimes which are in A075689. Next term of the sequence (if any) a(7) > 2750000. Is this sequence infinite?
No more terms < 1.76*10^10. - David Wasserman (wasserma(AT)spawar.navy.mil), Apr 06 2005
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FORMULA
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a(1)=4; smallest a(n) > a(n-1): a(1)+a(n), ..., a(n-1)+a(n) all are even interprimes.
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EXAMPLE
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a(1) = 4; a(1) + a(2) = 4 + 8 = 12 = ( 11 + 13 ) / 2, even interprime; a(1) + a(3) = 4 + 22 = 26 = ( 23 + 29 )/2, even interprime; a(2) + a(3) = 8 + 22 = 30 = ( 29 + 31 )/2, even interprime, etc.
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CROSSREFS
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Cf. A075689.
Sequence in context: A057583 A129788 A003684 this_sequence A026596 A083504 A075708
Adjacent sequences: A075685 A075686 A075687 this_sequence A075689 A075690 A075691
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KEYWORD
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nonn
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AUTHOR
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Zak Seidov (zakseidov(AT)yahoo.com), Sep 25 2002
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EXTENSIONS
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More terms from David Wasserman (wasserma(AT)spawar.navy.mil), Apr 06 2005
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