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 A249991 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. 1
 2, 3, 5, 10, 12, 13, 21, 26, 28, 39, 41, 46, 54, 65, 67, 82, 84, 85, 109, 114, 122, 137, 139, 160, 178, 179, 181, 222, 230, 235, 269, 274, 276, 313, 331, 336, 370, 381, 383, 424, 426, 437, 471, 476, 536, 541, 549, 554, 618, 629, 647, 704, 706, 707, 761, 818 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS 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. LINKS PROG (Python) TOP = 100000 a = range(TOP) for step in range(2, TOP): ..numBlocks = (len(a)-1) / step ..if numBlocks==0:  break ..a = a[:(1+numBlocks*step)] ..for pos in range(1, len(a), step): ....a[pos:pos+step] = a[pos+step-1:pos-1:-1] ..print str(a[1])+', ', ..a[1:] = a[2:] CROSSREFS Cf. A000960, A026239, A249990. Sequence in context: A192229 A233696 A002263 * A039022 A182402 A079251 Adjacent sequences:  A249988 A249989 A249990 * A249992 A249993 A249994 KEYWORD nonn AUTHOR Alex Ratushnyak, Nov 27 2014 STATUS approved

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Last modified April 3 13:53 EDT 2020. Contains 333197 sequences. (Running on oeis4.)