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A287010
Triangle T(n,m): floor(log(A002110(n))/log(prime(m))).
1
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
1,2
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#.
LINKS
Michael De Vlieger, Table of n, a(n) for n = 1..11325 (Rows 1 <= n <= 150).
EXAMPLE
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
...
MATHEMATICA
Table[With[{P = Product[Prime@ i, {i, n}]}, Floor@ Log[Prime@ #, P] & /@ Range@ n], {n, 20}] // Flatten
CROSSREFS
Sequence in context: A294317 A377802 A064277 * A144330 A141155 A204922
KEYWORD
nonn,easy,tabl
AUTHOR
Michael De Vlieger, Aug 31 2017
STATUS
approved