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%I #25 Mar 13 2022 16:58:53
%S 1,4,1,5,5,12,1,1,1,19,19,19,19,19,19,19,19,27,27,47,47,47,47,14,14,
%T 14,14,14,67,67,67,67,67,173,173,211,211,211,211,15,15,15,15,15,15,
%U 214,214,214,214,214,385,385,385,385,385,385,385,22,22,22,22,22,22,22
%N The numbers k arising in A352185.
%H Michael S. Branicky, <a href="/A352186/b352186.txt">Table of n, a(n) for n = 1..232</a>
%H Richard K. Guy, <a href="http://www.jstor.org/stable/2322320">What are the smallest arithmetic progressions of composite numbers?</a>, Amer. Math. Monthly, Vol. 93, No. 8 (1986), p. 627.
%o (Python)
%o from math import gcd
%o from sympy import isprime
%o from itertools import count, islice, takewhile
%o def comp(n): return not isprime(n)
%o def agen(): # generator of terms
%o n = 1
%o for m in count(2):
%o for k in range(1, m):
%o if gcd(k, m) != 1:
%o continue
%o ap = len(list(takewhile(comp, (i*m+k for i in count(1)))))
%o if ap >= n:
%o for i in range(n, ap+1):
%o yield k
%o n = ap + 1
%o print(list(islice(agen(), 64))) # _Michael S. Branicky_, Mar 12 2022
%Y Cf. A352185.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Mar 12 2022
%E a(24) and beyond from _Michael S. Branicky_, Mar 12 2022.
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