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Search: id:A068365
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| A068365 |
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Numbers n such that sigma(n)=phi((prime(n)+prime(n+1))/2). |
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+0
1
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| 14, 24, 308, 474, 690, 1242, 2970, 9690, 10340, 13110, 18270, 26400, 161880
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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Are there any odd numbers in the sequence?
There are no more terms up to 2500000. - Rick L. Shepherd (rshepherd2(AT)hotmail.com), Aug 29 2002
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PROGRAM
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(PARI) for(n=2, 2500000, if(sigma(n)==eulerphi((prime(n)+prime(n+1))/2), print1(n, ", ")))
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CROSSREFS
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Adjacent sequences: A068362 A068363 A068364 this_sequence A068366 A068367 A068368
Sequence in context: A111743 A141838 A140499 this_sequence A061923 A031075 A020227
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KEYWORD
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nonn
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AUTHOR
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Benoit Cloitre (benoit7848c(AT)orange.fr), Feb 28 2002
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EXTENSIONS
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More terms from Rick L. Shepherd (rshepherd2(AT)hotmail.com), Aug 29 2002
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