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 A342259 Numbers k such that omega(k-1) = omega(k)-1 and omega(k+1) = omega(k)+1, where omega(m) is the number of distinct primes dividing m, A001221(m). 2

%I #10 Mar 07 2021 13:14:53

%S 65,104,129,164,194,272,284,314,344,384,398,464,524,608,614,626,662,

%T 692,734,758,824,968,1025,1094,1172,1238,1280,1304,1364,1424,1448,

%U 1454,1532,1544,1595,1658,1664,1682,1724,1754,1832,1868,1869,1934,1952,2000,2001,2012

%N Numbers k such that omega(k-1) = omega(k)-1 and omega(k+1) = omega(k)+1, where omega(m) is the number of distinct primes dividing m, A001221(m).

%H Hugo Pfoertner, <a href="/A342259/b342259.txt">Table of n, a(n) for n = 1..10000</a>

%e a(1)=65: 64=2^6 (1 distinct prime 2), 65=5*13 (2 distinct primes 5 and 13, 66=2*3*11 (3 distinct primes 2, 3, and 11).

%o (PARI) for(n=3,2100,my(om=omega(n));if(omega(n-1)==om-1&&omega(n+1)==om+1,print1(n,", ")))

%Y Cf. A001221, A342258.

%K nonn

%O 1,1

%A _Hugo Pfoertner_, Mar 07 2021

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Last modified October 2 07:56 EDT 2023. Contains 365831 sequences. (Running on oeis4.)