A280005
Least prime p such that p^n + 1 is the product of n distinct primes.
Original entry on oeis.org
2, 3, 13, 43, 73, 47, 457, 1697, 109, 8161, 10429, 13183, 30089, 66569, 5281
Offset: 1
a(2) = 3; 3^2 + 1 = 2 * 5.
a(3) = 13; 13^3 + 1 = 2 * 7 * 157.
a(4) = 43; 43^4 + 1 = 2 * 17 * 193 * 521.
A363585
Least prime p such that p^n + 6 is the product of n distinct primes.
Original entry on oeis.org
5, 2, 23, 127, 71, 353, 1279, 3851, 3049, 18913, 47129, 352073, 696809
Offset: 1
a(1) = 5; 5^1 + 6 = 11.
a(2) = 2; 2^2 + 6 = 2 * 5.
a(3) = 23; 23^3 + 6 = 7 * 37 * 47.
a(4) = 127; 127^4 + 6 = 7 * 131 * 367 * 773.
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Table[b=6;y[a_]:=FactorInteger[Prime[a]^n+b];k=1;Monitor[Parallelize[While[True,If[And[Length[y[k]]==n,Count[Flatten[y[k]],1]==n],Break[]];k++];k],k]//Prime,{n,1,10}]
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a(n) = forprime(p=2, , my(f=factor(p^n + 6)); if (issquarefree(f) && (omega(f) == n), return(p)));
A368162
a(n) is the smallest number k > 0 such that bigomega(k^n + 1) = n.
Original entry on oeis.org
1, 3, 3, 43, 7, 32, 23, 643, 17, 207, 251, 3255, 255, 1568, 107
Offset: 1
a(5) = 7 is the smallest number of the set {k(i)} = {7, 14, 24, 26, 46, 51, ...} where k(i)^5 + 1 has exactly 5 prime factors counted with multiplicity.
A379768
a(n) is the smallest prime p such that omega(p^n + 1) = n.
Original entry on oeis.org
2, 3, 5, 43, 17, 47, 151, 1697, 59, 2153, 521, 13183, 30089, 66569, 761
Offset: 1
a(3) = 5 is the smallest prime of the set {p(i)} = {5, 11, 13, 19, 23, ...} where omega(p(i)^3 + 1) = 3.
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a[n_] := Module[{p = 2}, While[PrimeNu[p^n + 1] != n, p = NextPrime[p]]; p]; Print[Array[a, 11]]
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a(n) = forprime(p=2, oo, if(omega(p^n+1) == n, return(p)));
Showing 1-4 of 4 results.
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