cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A287010 Triangle T(n,m): floor(log(A002110(n))/log(prime(m))).

Original entry on oeis.org

1, 2, 1, 4, 3, 2, 7, 4, 3, 2, 11, 7, 4, 3, 3, 14, 9, 6, 5, 4, 4, 18, 11, 8, 6, 5, 5, 4, 23, 14, 9, 8, 6, 6, 5, 5, 27, 17, 11, 9, 8, 7, 6, 6, 6, 32, 20, 14, 11, 9, 8, 7, 7, 7, 6, 37, 23, 16, 13, 10, 10, 9, 8, 8, 7, 7, 42, 26, 18, 15, 12, 11, 10, 10, 9, 8, 8, 8
Offset: 1

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Author

Michael De Vlieger, Aug 31 2017

Keywords

Comments

Row n lists the largest power e of the prime divisors p_m of primorial p_n# such that p_m^e <= p_n#.

Examples

			For n = 3, A002110(n) = 30 = 2 * 3 * 5; floor(log_2(30)) = 4, floor(log_3(30)) = 3, floor(log_5(30)) = 2, thus row 3 = {4, 3, 2}.
Triangle begins:
   1:   1
   2:   2   1
   3:   4   3   2
   4:   7   4   3   2
   5:  11   7   4   3   3
   6:  14   9   6   5   4   4
   7:  18  11   8   6   5   5   4
   8:  23  14   9   8   6   6   5   5
   9:  27  17  11   9   8   7   6   6   6
  10:  32  20  14  11   9   8   7   7   7   6
  11:  37  23  16  13  10  10   9   8   8   7   7
  12:  42  26  18  15  12  11  10  10   9   8   8   8
  ...
		

Crossrefs

Programs

  • Mathematica
    Table[With[{P = Product[Prime@ i, {i, n}]}, Floor@ Log[Prime@ #, P] & /@ Range@ n], {n, 20}] // Flatten