A343809 Divide the positive integers into subsets of lengths given by successive primes, then reverse the order of terms in each subset.
2, 1, 5, 4, 3, 10, 9, 8, 7, 6, 17, 16, 15, 14, 13, 12, 11, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 58, 57, 56, 55, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, 44, 43, 42, 77, 76, 75, 74, 73, 72, 71, 70, 69, 68, 67, 66, 65, 64, 63, 62, 61, 60, 59
Offset: 1
Examples
From _Omar E. Pol_, Apr 30 2021: (Start) Written as an irregular triangle in which row lengths give A000040 the sequence begins: 2, 1; 5, 4, 3; 10, 9, 8, 7, 6; 17, 16, 15, 14, 13, 12, 11; 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18; 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29; 58, 57, 56, 55, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, 44, 43, 42; 77, 76, 75, 74, 73, 72, 71, 70, 69, 68, 67, 66, 65, 64, 63, 62, 61, 60, 59; ... (End)
Links
- Paolo Xausa, Table of n, a(n) for n = 1..10887 (rows n = 1..70 of triangle, flattened)
- Index entries for sequences that are permutations of the natural numbers
Crossrefs
Programs
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Maple
R:= NULL: t:= 1: for i from 1 to 20 do p:= ithprime(i); R:= R, seq(i,i=t+p-1..t,-1); t:= t+p; od: R; # Robert Israel, Apr 30 2021
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Mathematica
With[{nn=10},Reverse/@TakeList[Range[Total[Prime[Range[nn]]]],Prime[Range[nn]]]]//Flatten (* Harvey P. Dale, Apr 27 2022 *)
Comments