A348475 a(n) = Product_{k=1..A003056(n)} prime(T(n,k)), where T(n,k) = k-th term in row n of A235791.
2, 3, 10, 14, 33, 78, 170, 190, 483, 1218, 2046, 4070, 5330, 8385, 33558, 37842, 47082, 127490, 169510, 269445, 825630, 1250886, 1404858, 1969926, 4270910, 6988190, 13239105, 27506490, 29387490, 61019322, 74958702, 77319606, 191617790, 254235170, 715103895, 1549364190
Offset: 1
Examples
Row 3 of A235791 contains {3,1}, thus, a(3) = prime(3)*prime(1) = 5*2 = 10. Omar E. Pol's diagram of rows of A235791: . y row a(n) of A067255* a(n) Row _| -------------------------- 1 _|1| -> 1 = 2 2 _|2 _| -> .1 = 3 3 _|3 |1| -> 1.1 = 10 4 _|4 _|1| -> 1..1 = 14 5 _|5 |2 _| -> .1..1 = 33 6 _|6 _|2|1| -> 11...1 = 78 7 _|7 |3 |1| -> 1.1...1 = 170 8 _|8 _|3 _|1| -> 1.1....1 = 190 9 _|9 |4 |2 _| -> .1.1....1 = 483 10 _|10 _|4 |2|1| -> 11.1.....1 = 1218 11 _|11 |5 _|2|1| -> 11..1.....1 = 2046 12 _|12 _|5 |3 |1| -> 1.1.1......1 = 4070 13 _|13 |6 |3 _|1| -> 1.1..1......1 = 5330 14 _|14 _|6 _|3|2 _| -> .11..1.......1 = 8385 15 _|15 |7 |4 |2|1| -> 11.1..1.......1 = 33558 16 _|16 _|7 |4 |2|1| -> 11.1..1........1 = 37842 ... * we replace 0 with "." for clarity.
Links
- Michael De Vlieger, Table of n, a(n) for n = 1..10000
Programs
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Mathematica
Table[Times @@ Array[Prime@ Ceiling[(n + 1)/# - (# + 1)/2] &, Floor[(Sqrt[8 n + 1] - 1)/2]], {n, 35}] (* Use the b-file to generate k rows of A235791 *) With[{k = 120}, MapIndexed[Reverse[PrimePi /@ FactorInteger[#][[All, 1]]] &, Import["https://oeis.org/A348475/b348475.txt", "Data"][[1 ;; k, -1]]]] (* Michael De Vlieger, Oct 21 2021 *)
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