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A097975 Prime divisor of n which is >= sqrt(n). a(n) = 0 if no prime divisor of n is >= sqrt(n). 2
0, 2, 3, 2, 5, 3, 7, 0, 3, 5, 11, 0, 13, 7, 5, 0, 17, 0, 19, 5, 7, 11, 23, 0, 5, 13, 0, 7, 29, 0, 31, 0, 11, 17, 7, 0, 37, 19, 13, 0, 41, 7, 43, 11, 0, 23, 47, 0, 7, 0, 17, 13, 53, 0, 11, 0, 19, 29, 59, 0, 61, 31, 0, 0, 13, 11, 67, 17, 23, 0, 71, 0, 73, 37, 0, 19, 11, 13, 79, 0, 0, 41, 83 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Sequence also is the sum of distinct prime divisors of n which are >= sqrt(n). Only one prime divisor of n at most is >= squareroot of n.

LINKS

Diana Mecum, Table of n, a(n) for n = 1..1000

MATHEMATICA

Do[l = Select[Select[Divisors[n], PrimeQ], # >= Sqrt[n]&]; If[Length[l] == 0, Print[0], Print[l[[1]]]], {n, 1, 50}] (Propper)

CROSSREFS

Cf. A097974.

Sequence in context: A131470 A026235 A086281 * A130088 A078834 A039634

Adjacent sequences:  A097972 A097973 A097974 * A097976 A097977 A097978

KEYWORD

nonn

AUTHOR

Leroy Quet Sep 07 2004

EXTENSIONS

More terms from Ryan Propper (rpropper(AT)stanford.edu), Jul 24 2005

More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Jan 21 2006

Further terms from Diana Mecum (diana.mecum(AT)gmail.com), Jun 15 2007

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Last modified February 17 03:45 EST 2012. Contains 205978 sequences.