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A076302 Triangle T(n,k) = number of k-smooth divisors of n, read by rows. 0
1, 1, 2, 1, 1, 2, 1, 3, 3, 3, 1, 1, 1, 1, 2, 1, 2, 4, 4, 4, 4, 1, 1, 1, 1, 1, 1, 2, 1, 4, 4, 4, 4, 4, 4, 4, 1, 1, 3, 3, 3, 3, 3, 3, 3, 1, 2, 2, 2, 4, 4, 4, 4, 4, 4, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 3, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 2, 2, 2, 2, 4, 4, 4, 4, 4, 4, 4, 4 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

T(n,n)=A000005(n);

T(n,2)=A001511(n) for n>1; T(n,3)=A072078(n) for n>2.

LINKS

Table of n, a(n) for n=1..105.

Eric Weisstein's World of Mathematics, Divisor Function.

Eric Weisstein's World of Mathematics, Smooth Number.

EXAMPLE

Triangle begins:

.................. 1

................ 1...2

.............. 1...1...2

............ 1...3...3...3

.......... 1...1...1...1...2

........ 1...2...4...4...4...4

...... 1...1...1...1...1...1...2

.... 1...4...4...4...4...4...4...4

.. 1...1...3...3...3...3...3...3...3.

CROSSREFS

Sequence in context: A239000 A105248 A289495 * A104524 A233322 A233324

Adjacent sequences:  A076299 A076300 A076301 * A076303 A076304 A076305

KEYWORD

nonn,tabl

AUTHOR

Reinhard Zumkeller, Mar 14 2003

STATUS

approved

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Last modified November 23 17:10 EST 2020. Contains 338595 sequences. (Running on oeis4.)