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A078809
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Number of divisors of the average of consecutive odd primes.
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0
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3, 4, 3, 6, 4, 6, 4, 4, 8, 4, 4, 8, 6, 6, 8, 12, 7, 4, 12, 6, 5, 4, 4, 6, 8, 8, 12, 4, 16, 4, 4, 8, 15, 12, 8, 12, 8, 8, 10, 18, 8, 14, 8, 12, 4, 4, 9, 12, 8, 6, 20, 8, 4, 12, 8, 16, 4, 6, 8, 18, 18, 4, 16, 12, 15, 4, 12, 12, 8, 6, 6, 8, 8, 4, 4, 4, 8, 10, 12, 24, 8, 20, 6, 9, 4, 4, 8, 16, 8, 4, 8, 4
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| The first pair of consecutive odd primes is 3,5, with average = 4 and tau(4) = 3. Hence a(1) = 3. The second pair of consecutive odd primes is 5,7, with average = 6 and tau(6) = 4, so a(2) = 4.
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MATHEMATICA
| Table[DivisorSigma[0, (Prime[i] + Prime[i + 1])/2], {i, 2, 101}]
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CROSSREFS
| Sequence in context: A104076 A021295 A061112 * A097857 A176058 A110738
Adjacent sequences: A078806 A078807 A078808 * A078810 A078811 A078812
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KEYWORD
| easy,nonn
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AUTHOR
| Joseph L. Pe (Joseph_l_pe(AT)hotmail.com), Jan 11 2003
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