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A064678 Numbers k such that sopf(k) = sopfr(k+1), where sopf(k) = A008472(k) and sopfr(k) = A001414(k). 1
5, 15, 77, 99, 104, 153, 369, 492, 539, 714, 1330, 2491, 4191, 5405, 5831, 5959, 6556, 6579, 6723, 8463, 9424, 12221, 12351, 12726, 13419, 14587, 21716, 24432, 24880, 24895, 26642, 30267, 31487, 33019, 35456, 38324, 43215, 43802, 44831, 45524 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..500 from Harry J. Smith)

PROG

(PARI) sopf(n)= { local(f, s=0); f=factor(n); for(i=1, matsize(f)[1], s+=f[i, 1]); return(s) } sopfr(n)= { local(f, s=0); f=factor(n); for(i=1, matsize(f)[1], s+=f[i, 1]*f[i, 2]); return(s) } { n=0; for (m=1, 10^9, if (sopf(m)==sopfr(m + 1), write("b064678.txt", n++, " ", m); if (n==500, break)) ) } \\ Harry J. Smith, Sep 22 2009

CROSSREFS

Cf. A001414 (sopfr), A008472 (sopf).

Sequence in context: A149655 A032122 A220818 * A088935 A183937 A275971

Adjacent sequences:  A064675 A064676 A064677 * A064679 A064680 A064681

KEYWORD

easy,nonn

AUTHOR

Jason Earls, Oct 10 2001

STATUS

approved

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Last modified September 20 23:24 EDT 2020. Contains 337265 sequences. (Running on oeis4.)