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%I #18 Oct 10 2023 05:04:22
%S 1,3,0,0,5,-1,-7,1,-8,-80,-69,-81,-1053,-1039,-1054,-16864,-16847,
%T -16865,-320435,-320415,-320436,-7049592,-7049569,-7049593,-176239825,
%U -176239799,-176239826,-4934715128,-4934715099,-4934715129,-152976168999,-152976168967,-152976169000
%N a(1) = 1, then add, subtract and multiply 2, 3, 4; 5, 6, 7; ... in that order.
%F a(1)=1; for n > 1,
%F a(n) = a(n-1) + n if n mod 3 = 2,
%F a(n-1) - n if n mod 3 = 0,
%F a(n-1) * n if n mod 3 = 1.
%e a(2) = 1 + 2 = 3;
%e a(3) = 3 - 3 = 0;
%e a(4) = 0 * 4 = 0.
%t FoldList[If[Mod[#2, 3]==2, #1+#2, If[Mod[#2, 3]==0, #1-#2, #1*#2]]&, 1, Range[2, 33]] (* _James C. McMahon_, Oct 09 2023 *)
%o (Python)
%o from itertools import count, islice
%o def A362271_gen(): # generator of terms
%o yield (a:=1)
%o for n in count(2,3):
%o yield (a:=a+n)
%o yield (a:=a-n-1)
%o yield (a:=a*(n+2))
%o A362271_list = list(islice(A362271_gen(),20)) # _Chai Wah Wu_, Apr 19 2023
%Y Other operation orders: A077382, A077383, A362269, A362270, A362272.
%K sign
%O 1,2
%A _James C. McMahon_, Apr 13 2023
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