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%I #16 Jul 07 2023 18:57:24
%S 6,8,12,14,20,24,38,54,62,80,90,110,138,150,164,168,192,194,272,278,
%T 314,332,348,398,402,434,500,572,642,644,720,728,762,798,812,860,864,
%U 878,920,992,1020,1022,1070,1092,1098,1118,1130,1182,1202,1230,1260,1308
%N Numbers k such that k^3-1 is an odd semiprime.
%H Hugo Pfoertner, <a href="/A096175/b096175.txt">Table of n, a(n) for n = 1..10000</a>
%H Dario A. Alpern, <a href="https://www.alpertron.com.ar/ECM.HTM">Factorization using the Elliptic Curve Method</a>
%e a(1)=6 because 6^3 - 1 = 216 - 1 = 215 = 5*43.
%o (PARI)
%o forstep (k=2,1310,2,if(bigomega(k^3-1)==2,print1(k,", ")))
%o \\ _Hugo Pfoertner_, Nov 28 2017
%Y Cf. A096173: k^3+1 is an odd semiprime; A081257: largest prime factor of k^3-1; A096176 (k^3-1)/(k-1) is prime; A046315.
%K nonn
%O 1,1
%A _Hugo Pfoertner_, Jun 22 2004
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