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%I #22 Oct 10 2023 05:04:33
%S 1,2,-1,3,15,9,16,128,119,129,1419,1407,1420,19880,19865,19881,337977,
%T 337959,337978,6759560,6759539,6759561,155469903,155469879,155469904,
%U 4042217504,4042217477,4042217505,117224307645,117224307615,117224307646,3751177844672,3751177844639
%N a(1) = 1, then multiply, subtract, and add 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 = 2;
%e a(3) = 2 - 3 = -1;
%e a(4) = -1 + 4 = 3.
%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 A362272_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 A362272_list = list(islice(A362272_gen(),20)) # _Chai Wah Wu_, Apr 19 2023
%Y Other operation orders: A077382, A077383, A362269, A362270, A362271.
%K sign
%O 1,2
%A _James C. McMahon_, Apr 19 2023
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