|
%I #11 Nov 13 2017 00:00:05
%S 23,610,1162,1243,1651,7385,13066,37129,38123,41194,41361,48511,59452,
%T 72179,83151,87375,98877,103528,126497,138190,141037,148657,157994,
%U 162410,175077,262788,296482,299398,351226,354321,418134,425099,452130,465254,470494
%N 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).
%H Robert G. Wilson v, <a href="/A294995/b294995.txt">Table of n, a(n) for n = 1..1179</a>
%e 610 is in the sequence since sopfr(608) = 29, sopfr(609) = 39 and sopfr(610) = 68 = 39 + 29.
%t f[n_]:=Plus @@ Times @@@ FactorInteger@ n; Select[Range[10^5], f[#]==f[#-1]+f[#-2] &]
%o (PARI) sopfr(n,f=factor(n))=f[,1]~*f[,2]
%o 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
%Y Cf. A001414, A075565.
%K nonn
%O 1,1
%A _Amiram Eldar_, Nov 12 2017
|
