Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #9 Sep 08 2022 08:46:19
%S 1,8,15,22,36,50,57,64,78,85,92,99,106,120,134,141,148,155,162,169,
%T 176,183,190,204,218,225,232,246,253,260,267,274,288,295,302,309,316,
%U 323,330,344,351,358,365,372,386,393,400,407,414,428,435,442,456,470,477,484,498
%N Nonprimes of the form 7*k + 1.
%C Subsequence of A018252.
%t DeleteCases[7 Range[0, 200] + 1, _?PrimeQ]
%o (Magma) [n: n in [1..500 by 7] | not IsPrime(n)];
%Y Cf. A016993, A091113, A091300, A140444, A291745, A291746.
%K nonn,easy
%O 1,2
%A _Vincenzo Librandi_, Aug 31 2017