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A060175
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Table T(n,k) by antidiagonals of exponent of largest power of k-th prime which divides n.
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9
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0, 0, 1, 0, 0, 0, 0, 0, 1, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0
(list;
table;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,10
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LINKS
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FORMULA
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EXAMPLE
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a(12,1) = 2 since 4 = 2^2 = p_1^2 divides 12 but 8 = 2^3 does not.
a(12,2) = 1 since 3 = p_2 divides 12 but 9 = 3^2 does not.
See also examples in A249344, which is transpose of this array.
The top-left corner of the array:
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ...
1, 0, 0, 0, 0, 0, 0, 0, 0, 0, ...
0, 1, 0, 0, 0, 0, 0, 0, 0, 0, ...
2, 0, 0, 0, 0, 0, 0, 0, 0, 0, ...
0, 0, 1, 0, 0, 0, 0, 0, 0, 0, ...
...
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MATHEMATICA
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T[n_, k_] := IntegerExponent[n, Prime[k]];
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PROG
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(Scheme)
(define (A249344bi row col) (let ((p (A000040 row))) (let loop ((n col) (i 0)) (cond ((not (zero? (modulo n p))) i) (else (loop (/ n p) (+ i 1)))))))
(Python)
from sympy import prime
def a(n, k):
p=prime(n)
i=z=0
while p**i<=k:
if k%(p**i)==0: z=i
i+=1
return z
for n in range(1, 10): print([a(n - k + 1, k) for k in range(1, n + 1)]) # Indranil Ghosh, Jun 24 2017
(PARI) a(n, k) = valuation(n, prime(k)); \\ Michel Marcus, Jun 24 2017
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CROSSREFS
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KEYWORD
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AUTHOR
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EXTENSIONS
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Erroneous example corrected and more terms computed by Antti Karttunen, Oct 28 2014
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STATUS
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approved
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