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A064142 Sum of all distinct primes dividing central binomial coefficient C(n,[n/2]). 1
0, 2, 3, 5, 7, 7, 12, 14, 12, 12, 23, 23, 29, 29, 32, 34, 48, 48, 62, 62, 61, 61, 81, 81, 73, 73, 69, 69, 98, 98, 127, 129, 123, 123, 130, 130, 148, 148, 161, 161, 195, 195, 227, 227, 204, 204, 251, 251, 253, 253, 257, 257, 307, 307, 323, 323, 316, 316, 367, 367 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

LINKS

Harry J. Smith, Table of n, a(n) for n=1,...,1000

FORMULA

a(n)=A008472[A001405(n)]

PROG

(PARI) sopf(n)= { local(f, s=0); f=factor(n); for(i=1, matsize(f)[1], s+=f[i, 1]); return(s) } { for (n=1, 1000, write("b064142.txt", n, " ", sopf(binomial(n, n\2))) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Sep 08 2009]

CROSSREFS

A008472, A001405.

Sequence in context: A039734 A020482 A060308 * A067792 A119317 A198424

Adjacent sequences:  A064139 A064140 A064141 * A064143 A064144 A064145

KEYWORD

nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu), Sep 11 2001

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Last modified February 16 21:15 EST 2012. Contains 205971 sequences.