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%I #10 May 07 2022 09:26:35
%S 31,175,1039,1471,2191,4495,6223,8815,13135,20479,22639,26815,30703,
%T 36031,37327,45967,52879,53743,54031,66703,78799,89023,108175,122863,
%U 125887,132799,135679,136687,160879,177151,178159,181183,184207,188095
%N Terms k of A002977 such that both (k-1)/2 and (k-1)/3 are also terms of A002977.
%H Amiram Eldar, <a href="/A085249/b085249.txt">Table of n, a(n) for n = 1..1000</a>
%e A002977(51) = 175: (175-1)/2 = 82 = A002977(28) and (175-1)/3 = 58 = A002977(22), therefore 175 is a term.
%t seq[max_] := Module[{s = Flatten[NestWhileList[Flatten[{2*# + 1, 3*# + 1}] &, 1, Min[#1] < max &]], t}, t = Union[Select[s, # <= max &]]; Select[t, MemberQ[t, (# - 1)/2] && MemberQ[t, (# - 1)/3] &]]; seq[200000] (* _Amiram Eldar_, May 07 2022 *)
%Y Subsequence of A016921 and A002977.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Aug 11 2003
%E More terms from _Ray Chandler_, Sep 06 2003