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A228003
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Places of records of A227321.
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1
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0, 4, 11, 13, 19, 31, 43, 61, 73, 103, 109, 139, 151, 181, 193, 199, 211, 223, 229, 241, 271, 283, 313, 349, 379, 409, 421, 433, 439, 463, 523, 571, 601, 613, 619, 631, 643, 649
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listen;
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OFFSET
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1,2
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COMMENTS
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Records of A227321 are 3, 4, 5, 8, 11, 17, 23, 32, 38,....
The first 3 nonprimes are a(1)=0, a(2)=4, a(38)=649.
The sequence contains all greaters of twin primes more than 7 (see A006512).
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LINKS
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FORMULA
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For n>=4, A227321(a(n)) = (a(n) + 3)/2.
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CROSSREFS
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KEYWORD
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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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