A124945 Numbers k such that k and k+10 are 10-almost primes.
506240, 789750, 1325312, 1567350, 1761750, 1944800, 2450240, 2579840, 3004928, 3013686, 3093750, 3153654, 3713526, 3844736, 3906240, 4024566, 4394240, 5244416, 5402240, 5431040, 6208640, 6310710, 6932790, 7053750, 7352694, 7585974, 8005878, 8043776, 8099190
Offset: 1
Keywords
Examples
506240=2^7*5*7*113, 506250=2*3^4*5^5; 789750=2*3^5*5^3*13, 789760=2^8*5*617; 1325312=2^8*31*167, 1325322=2*3^8*101; 1567350=2*3^6*5^2*43, 1567360=2^7*5*31*79.
Links
- Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
Programs
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Mathematica
Select[Range[10^7],PrimeOmega[#]==PrimeOmega[#+10]==10&] (* James C. McMahon, Dec 14 2024 *)
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PARI
isok(n) = (bigomega(n) == 10) && (bigomega(n+10) == 10); \\ Michel Marcus, Oct 11 2013
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PARI
P=prod(i=1,25,prime(i))^10; v=List(); for(n=1,1e6, g1=gcd(n,P); o1=bigomega(g1); if(o1<5,next); g2=gcd(n+10,P); o2=bigomega(g2); if(o2>=5 && o1+bigomega(n/g1)==10 && o2+bigomega((n+10)/g2)==10, listput(v,n))); Vec(v) \\ Charles R Greathouse IV, Oct 11 2013
Extensions
More terms from Michel Marcus, Oct 11 2013
Comments