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A349192
Irregular triangle T(m,k) = inverse permutation of S(m,k) = A349191 read as an irregular triangle.
2
1, 2, 1, 4, 2, 1, 3, 6, 2, 1, 4, 3, 5, 8, 2, 1, 6, 4, 7, 3, 5, 11, 3, 2, 8, 5, 10, 4, 6, 1, 7, 9, 15, 3, 2, 11, 6, 13, 5, 7, 1, 9, 12, 4, 8, 10, 14, 18, 3, 2, 14, 7, 16, 6, 8, 1, 10, 15, 4, 9, 12, 17, 5, 11, 13, 24, 4, 3, 19, 10, 21, 9, 11, 2, 14, 20, 6, 12, 16
OFFSET
1,2
COMMENTS
We find k at S(m,k) where S is A349191 read as an irregular triangle. Alternatively, we find prime(k) at U(m,k) where U is A348907 read as an irregular triangle.
LINKS
Michael De Vlieger, Table of n, a(n) for n = 1..10237 (rows 1 <= n <= 35, flattened)
Michael De Vlieger, Log-log scatterplot of T(m,k) 1 <= m <= 36.
FORMULA
Row lengths are in A338237.
EXAMPLE
First rows of T(m,k):
m\k 1 2 3 4 5 6 7 8 9 10 11
-----------------------------------------------
1: 1
2: 2 1
3: 4 2 1 3
4: 6 2 1 4 3 5
5: 8 2 1 6 4 7 3 5
6: 11 3 2 8 5 10 4 6 1 7 9
... (End)
MATHEMATICA
c = 0; Flatten@ Map[Table[If[k == 1, Length[#] + 1, FirstPosition[#, k - 1][[1]]], {k, If[IntegerQ@ #, # + 1, 1] &@ Max[#]}] &, {{}}~Join~Most@ SplitBy[Reap[Do[Set[a[i], If[PrimeQ[i], i; c++, a[i - c]]]; Sow[a[i]], {i, 2, 100}]][[-1, -1]], # == 0 &][[2 ;; -1 ;; 2]]]
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Michael De Vlieger, Nov 09 2021
STATUS
approved