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A294995
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Numbers n such that sopfr(n) = sopfr(n-1) + sopfr(n-2), where sopfr is the sum of prime factors of n with multiplicity (A001414).
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7
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23, 610, 1162, 1243, 1651, 7385, 13066, 37129, 38123, 41194, 41361, 48511, 59452, 72179, 83151, 87375, 98877, 103528, 126497, 138190, 141037, 148657, 157994, 162410, 175077, 262788, 296482, 299398, 351226, 354321, 418134, 425099, 452130, 465254, 470494
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OFFSET
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1,1
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LINKS
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EXAMPLE
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610 is in the sequence since sopfr(608) = 29, sopfr(609) = 39 and sopfr(610) = 68 = 39 + 29.
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MATHEMATICA
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f[n_]:=Plus @@ Times @@@ FactorInteger@ n; Select[Range[10^5], f[#]==f[#-1]+f[#-2] &]
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PROG
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(PARI) sopfr(n, f=factor(n))=f[, 1]~*f[, 2]
list(lim)=my(v=List(), a=0, b=2, c); forfactored(k=3, lim\1, c=sopfr(k[2]); if(c==a+b, listput(v, k[1])); a=b; b=c); Vec(v) \\ Charles R Greathouse IV, Nov 12 2017
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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