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A235168
Triangle read by rows: row n gives digits of n in primorial base.
18
0, 1, 1, 0, 1, 1, 2, 0, 2, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 2, 0, 1, 2, 1, 2, 0, 0, 2, 0, 1, 2, 1, 0, 2, 1, 1, 2, 2, 0, 2, 2, 1, 3, 0, 0, 3, 0, 1, 3, 1, 0, 3, 1, 1, 3, 2, 0, 3, 2, 1, 4, 0, 0, 4, 0, 1, 4, 1, 0, 4, 1, 1, 4, 2, 0, 4, 2, 1, 1, 0, 0, 0
OFFSET
0,7
COMMENTS
T(n,k) = A108731(n,k) for k=0..23.
a(n) = A108731(n) for n=0..63, when both tables are seen as flattened lists.
T(n,k) < 10 for k = 1..A235224(n) and n < 2100 = 10 * 7#.
When read from right to left, the row n gives exponents for successive primes 2, 3, 5, 7, 11, etc., in A276086(n). - Antti Karttunen, Mar 15 2021
EXAMPLE
. n | .. + _*7# + _*5# + _*3# + _*2# + _*1# | row(n)
. ---------+---------------------------------------+---------------------
. 10 | 1*6 + 2*2 + 0*1 | [1,2,0], A276086(10) = 5 * 3^2
. 100 | 3*30 + 1*6 + 2*2 + 0*1 | [3,1,2,0]
. 1000 | 4*210 + 5*30 + 1*6 + 2*2n + 0*1 | [4,5,1,2,0]
. 2099 | 9*210 + 6*30 + 4*6 + 2*2 + 1*1 | [9,6,4,2,1]
. 2100 | 10*210 + 0*30 + 0*6 + 0*2 + 0*1 | [10,0,0,0,0]
. 10000 | 4*2310 + 3*210 + 4*30 + 1*6 + 2*2 | [4,3,4,1,2,0]
. 100000 | 3*30030+4*2310+3*210+1*30+1*6+2*2+0*1 | [3,4,3,1,1,2,0]
. 1000000 | | [1,16,3,9,6,1,2,0]
. 10000000 | | [1,0,10,0,0,0,1,2,0]
. 1000000 = 1*510510+16*30030+3*2310+9*210+6*30+1*6+2*2+0*1
. 10000000 = 1*9699690+0*510510+10*30030+0*2310+0*210+0*30+1*6+2*2+0*1
MATHEMATICA
row[n_] := Module[{k = n, p = 2, s = {}, r}, While[{k, r} = QuotientRemainder[k, p]; k != 0 || r != 0, AppendTo[s, r]; p = NextPrime[p]]; Reverse[s]]; row[0] = {0}; Array[row, 31, 0] // Flatten (* Amiram Eldar, Mar 11 2024 *)
PROG
(Haskell)
a235168 n k = a235168_row n !! k
a235168_row 0 = [0]
a235168_row n = t n $ reverse $ takeWhile (<= n) a002110_list
where t 0 [] = []
t x (b:bs) = x' : t m bs where (x', m) = divMod x b
a235168_tabf = map a235168_row [0..]
CROSSREFS
Cf. A002110, A049345, A108731, A235224 (row lengths), A276086.
Sequence in context: A076626 A182886 A108731 * A060950 A039976 A287267
KEYWORD
nonn,tabf,base,look
AUTHOR
Reinhard Zumkeller, Jan 05 2014
STATUS
approved