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Search: id:A078455
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| A078455 |
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a(1) = 2. For n>1, a(n) = smallest m such that m == 0 (mod prime(n)), m + 1 == 0 (mod prime(n+1)) and m-1 == 0 (mod prime(n-1)). |
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+0
1
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| 2, 9, 55, 21, 792, 1937, 170, 4047, 115, 9454, 31930, 23902, 2665, 44978, 65189, 122483, 134992, 170983, 220028, 101104, 85556, 27887, 296725, 629141, 154327, 546208, 46865, 950588, 1043893, 1548891, 70739, 702946, 2389965, 1513988
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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A subsequence of the mean of three consecutive numbers divisible by three consecutive primes (A-number?).
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EXAMPLE
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a(7) = 170. prime(7) = 17, prime(7-1) = 13, prime(7+1)=19 and 17 | 170, 19 | 171, 13 | 169 and 170 is the smallest such number.
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MATHEMATICA
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(* First do <<NumberTheory`NumberTheoryFunctions` *) a[1]=2; a[n_] := ChineseRemainder[{1, 0, Prime[n+1]-1}, Prime/@Range[n-1, n+1]]
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CROSSREFS
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Sequence in context: A064151 A075679 A001757 this_sequence A036074 A009363 A069564
Adjacent sequences: A078452 A078453 A078454 this_sequence A078456 A078457 A078458
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KEYWORD
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easy,nonn
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AUTHOR
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Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Dec 23 2002
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EXTENSIONS
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More terms from Jim Nastos (nastos(AT)gmail.com), Feb 19 2003 and Dean Hickerson (dean.hickerson(AT)yahoo.com), Feb 23 2003
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