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%I #9 May 13 2017 18:06:16
%S 26,39,74,77,118,119,178,194,219,235,299,301,329,377,381,454,471,502,
%T 535,565,566,634,679,703,721,779,842,886,893,914,973,995,998,1006,
%U 1126,1174,1227,1282,1294,1317,1337,1343,1389,1418,1457,1563,1577,1623,1642
%N Semiprime function n -> A001358(n) applied three times to n.
%F a(n) = A001358(A001358(A001358(n))).
%e a(1) = semiprime(semiprime(semiprime(1))) = semiprime(semiprime(4)) = semiprime(10) = 26.
%t f[n_] := Plus @@ Flatten[ Table[ # [[2]], {1}] & /@ FactorInteger[ n]]; t = Select[ Range[ 1700], f[ # ] == 2 &]; Table[ Nest[ t[[ # ]] &, n, 3], {n, 50}] (* _Robert G. Wilson v_, Apr 30 2005 *)
%Y Cf. A001358, A007097, A091022, A105998, A105999.
%K easy,nonn
%O 1,1
%A _Jonathan Vos Post_, Apr 29 2005
%E Corrected and extended by _Robert G. Wilson v_, Apr 30 2005
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