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A064675 Numbers k such that sopfr(k) = sopf(k+1), where sopf(k) = A008472(k) and sopfr(k) = A001414(k). 1
5, 27, 77, 714, 836, 948, 1449, 4185, 4624, 5405, 5560, 8476, 8855, 10175, 16932, 17080, 18655, 20450, 20600, 21183, 26642, 28809, 31524, 35631, 37828, 37881, 40081, 47544, 48203, 49240, 52155, 52554, 53192, 63344, 63426, 63665, 79118 (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 (sopfr(m)==sopf(m + 1), write("b064675.txt", n++, " ", m); if (n==500, break)) ) } \\ Harry J. Smith, Sep 21 2009

CROSSREFS

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

Sequence in context: A121876 A137116 A137117 * A135713 A085740 A212783

Adjacent sequences:  A064672 A064673 A064674 * A064676 A064677 A064678

KEYWORD

nonn

AUTHOR

Jason Earls, Oct 10 2001

STATUS

approved

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Last modified September 22 22:24 EDT 2020. Contains 337291 sequences. (Running on oeis4.)