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A120374 Median of prime divisors of 2n+1 (with multiplicity). 0
3, 5, 7, 3, 11, 13, 4, 17, 19, 5, 23, 5, 3, 29, 31, 7, 6, 37, 8, 41, 43, 3, 47, 7, 10, 53, 8, 11, 59, 61, 3, 9, 67, 13, 71, 73, 5, 9, 79, 3, 83, 11, 16, 89, 10, 17, 12, 97, 3, 101, 103, 5, 107, 109, 20, 113, 14, 3, 12, 11, 22, 5, 127, 23, 131, 13, 3, 137, 139, 25, 12, 17, 7, 149, 151 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..75.

EXAMPLE

165 = 3*5*11, an odd number of prime divisors; the middle one is 5, so a(165) = 5. 315 = 3*3*5*7, an even number of prime divisors; the middle two are 3 and 5; their mean is 4, so a(315) = 4.

CROSSREFS

Cf. A088836 (first difference at 2n+1 = 45).

Sequence in context: A130140 A051417 A090368 * A088836 A076565 A286517

Adjacent sequences:  A120371 A120372 A120373 * A120375 A120376 A120377

KEYWORD

nonn

AUTHOR

Franklin T. Adams-Watters, Jun 27 2006

STATUS

approved

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Last modified February 24 12:34 EST 2018. Contains 299622 sequences. (Running on oeis4.)