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A352191 Records in A352187. 2

%I

%S 1,2,4,6,9,12,15,18,21,24,25,30,33,36,39,42,51,56,57,77,121,207,333,

%T 345,371,391,469,871,1111,1121,1341,1557,1719,2043,2051,2367,3421,

%U 3951,4527,6127,6849,10307,11007,11061,11079,11133,11511,14113,16753,16839,16911,17973,18153,19161,27731,28831,29447,36949,46783,49093,49577

%N Records in A352187.

%o (Python)

%o from math import gcd

%o from itertools import count, islice

%o from sympy import primefactors

%o def A352191_gen(): # generator of terms

%o bset, blist, mmax, c = {1,2}, [1,2], 3, 2

%o yield from blist

%o while True:

%o for m in count(mmax):

%o if gcd(m,blist[-1]) > 1 and m not in bset:

%o if all(blist[-2] % p == 0 for p in primefactors(blist[-1])) or gcd(m,blist[-2]) == 1:

%o if m > c:

%o yield m

%o c = m

%o blist = [blist[-1],m]

%o bset.add(m)

%o while mmax in bset:

%o mmax += 1

%o break

%o A352191_list = list(islice(A352191_gen(),30)) # _Chai Wah Wu_, Mar 14 2022

%Y Cf. A352187, A352192.

%K nonn

%O 1,2

%A _N. J. A. Sloane_, Mar 13 2022

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Last modified February 6 04:21 EST 2023. Contains 360097 sequences. (Running on oeis4.)