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 A078809 Number of divisors of the average of consecutive odd primes. 1
 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; text; internal format)
 OFFSET 1,1 LINKS Harvey P. Dale, Table of n, a(n) for n = 1..1000 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. MATHEMATICA Table[DivisorSigma[0, (Prime[i] + Prime[i + 1])/2], {i, 2, 101}] DivisorSigma[0, #]&/@(Mean/@Partition[Prime[Range[2, 100]], 2, 1]) (* Harvey P. Dale, Jul 06 2021 *) CROSSREFS Sequence in context: A242801 A021295 A061112 * A245218 A097857 A176058 Adjacent sequences:  A078806 A078807 A078808 * A078810 A078811 A078812 KEYWORD easy,nonn AUTHOR Joseph L. Pe, Jan 11 2003 STATUS approved

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Last modified September 22 09:47 EDT 2021. Contains 347606 sequences. (Running on oeis4.)