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A343809
Divide the positive integers into subsets of lengths given by successive primes, then reverse the order of terms in each subset.
3
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
1,1
COMMENTS
From Omar E. Pol, Apr 30 2021: (Start)
Irregular triangle read by rows T(n,k) in which row n lists the next p positive integers in decreasing order, where p is the n-th prime, with n >= 1.
The triangle has the following properties:
Column 1 gives the nonzero terms of A007504.
Column 2 gives A237589.
Column 3 gives A071148.
Column 4 gives the terms > 2 of A343859.
Column 5 gives the absolute values of the terms < -1 of A282329.
Column 6 gives the terms > 7 of A082548.
Column 7 gives the terms > 6 of A115030.
Records are in the column 1.
Indices of records are in the right border.
Right border gives A014284.
Row lengths give A000040.
Row products give A078423.
Row sums give A034956. (End)
FORMULA
T(n,k) = A007504(n) - k + 1, with n >= 1 and 1 <= k <= A000040(n). - Omar E. Pol, May 01 2021
EXAMPLE
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)
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
MATHEMATICA
With[{nn=10}, Reverse/@TakeList[Range[Total[Prime[Range[nn]]]], Prime[Range[nn]]]]//Flatten (* Harvey P. Dale, Apr 27 2022 *)
KEYWORD
nonn,tabf
AUTHOR
Paolo Xausa, Apr 30 2021
STATUS
approved