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A134557 Triangle multiplicatively decoded from A039716, the factorials of the prime numbers, read by rows. 0
1, 1, 1, 3, 1, 1, 4, 2, 1, 1, 8, 4, 2, 1, 1, 10, 5, 2, 1, 1, 1, 15, 6, 3, 2, 1, 1, 1, 16, 8, 3, 2, 1, 1, 1, 1, 19, 9, 4, 3, 2, 1, 1, 1, 1, 25, 13, 6, 4, 2, 2, 1, 1, 1, 1, 26, 14, 7, 4, 2, 2, 1, 1, 1, 1, 1, 34, 17, 8, 5, 3, 2, 2, 1, 1, 1, 1, 1, 38, 18, 9, 5, 3, 3, 2, 2, 1, 1, 1, 1, 1, 39, 19, 9, 6, 3, 3, 2 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,4

REFERENCES

N. J. A. Sloane, The Encyclopedia of Integer Sequences. New York: Academic Press (1995): Fig. M1722, "Multiplicative encoding of a triangular array"

LINKS

Table of n, a(n) for n=1..98.

PlanetMath, Multiplicative encoding

EXAMPLE

Triangle begins:

{1}

{1, 1}

{3, 1, 1}

{4, 2, 1, 1}

{8, 4, 2, 1, 1}

{10, 5, 2, 1, 1, 1}

{15, 6, 3, 2, 1, 1, 1}

{16, 8, 3, 2, 1, 1, 1, 1}

Row 5 of the triangle is 8, 4, 2, 1, 1 because A039716(5) = 39916800 and 39916800 = 2^8 * 3^4 * 5^2 * 7^1 * 11^1.

MATHEMATICA

ColumnForm[Table[Take[Flatten[FactorInteger[Prime[n]! ]], {2, 2n, 2}], {n, 15}], Center]

CROSSREFS

Cf. A039716.

Sequence in context: A023579 A023577 A188139 * A290342 A219842 A134264

Adjacent sequences:  A134554 A134555 A134556 * A134558 A134559 A134560

KEYWORD

nonn,tabl

AUTHOR

Alonso del Arte, Jan 22 2008

STATUS

approved

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Last modified February 24 03:21 EST 2018. Contains 299595 sequences. (Running on oeis4.)