

A078835


Sum of the divisors of the average of consecutive odd primes.


0



7, 12, 13, 28, 24, 39, 32, 42, 72, 54, 56, 96, 78, 93, 120, 168, 127, 96, 195, 140, 121, 132, 128, 156, 216, 192, 280, 152, 360, 176, 204, 288, 403, 372, 288, 378, 288, 324, 372, 546, 384, 508, 336, 468, 252, 256, 403, 560, 384, 420, 744, 504, 384, 588, 480
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OFFSET

1,1


LINKS



FORMULA



EXAMPLE

The first pair of consecutive odd primes is 3,5, with average = 4 and sigma(4) = 7. Hence a(1) = 7. The second pair of consecutive odd primes is 5,7, with average = 6 and sigma(6) = 12, so a(2) = 12.


MATHEMATICA

Table[DivisorSigma[1, (Prime[i] + Prime[i + 1])/2], {i, 2, 101}]
DivisorSigma[1, Mean[#]]&/@Partition[Prime[Range[2, 60]], 2, 1] (* Harvey P. Dale, Dec 07 2013 *)


CROSSREFS



KEYWORD

easy,nonn


AUTHOR



STATUS

approved



