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A055737
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Number of prime triples < 10^n, where a prime triple means 3 successive primes of the form {p, p+2, p+4} or {p, p+4, p+6}.
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1
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0, 8, 30, 112, 507, 2837, 17220, 111156, 759256, 5425573, 40174725, 305689269, 2379622234, 18887841658
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OFFSET
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1,2
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COMMENTS
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For this sequence all three members of the triple must be below the 10^n bound. - Sean A. Irvine, Apr 04 2022
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REFERENCES
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J. Recreational Math., vol. 23, No. 2, 1991, p. 97.
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LINKS
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MATHEMATICA
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x=168; a=Table[ Prime[ n ], {n, 1, x} ] c=0; Do[ If[ a[[ n ]]+6==a[ [ n+2 ] ], c++ ], {n, 1, x-2} ]; c # the values of x to use are given by A006880
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CROSSREFS
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KEYWORD
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more,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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