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Start with the natural numbers, reverse the order in each pair, skip one number, reverse the order in each triple, skip one number, and so on.
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%I #13 Jun 24 2022 20:00:56

%S 2,3,5,10,12,13,21,26,28,39,41,46,54,65,67,82,84,85,109,114,122,137,

%T 139,160,178,179,181,222,230,235,269,274,276,313,331,336,370,381,383,

%U 424,426,437,471,476,536,541,549,554,618,629,647,704,706,707,761,818

%N Start with the natural numbers, reverse the order in each pair, skip one number, reverse the order in each triple, skip one number, and so on.

%C Start with the natural numbers. Reverse the order of numbers in each pair. Skip one number. In the remainder (that is, "1, 4, 3, 6, 5, 8, 7, 10, 9, 12, 11,...") reverse the order in each triple. Skip one number. In the remainder (it starts with "4, 1, 8, 5, 6, 9, 10, 7") reverse the order in each tetrad. Skip one number. And so on.

%o (Python)

%o TOP = 100000

%o a = range(TOP)

%o for step in range(2,TOP):

%o ..numBlocks = (len(a)-1) / step

%o ..if numBlocks==0: break

%o ..a = a[:(1+numBlocks*step)]

%o ..for pos in range(1,len(a),step):

%o ....a[pos:pos+step] = a[pos+step-1:pos-1:-1]

%o ..print str(a[1])+',',

%o ..a[1:] = a[2:]

%Y Cf. A000960, A026239, A249990.

%Y Partial sums of A057031.

%K nonn

%O 1,1

%A _Alex Ratushnyak_, Nov 27 2014