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A212176 Row n of table lists exponents in canonical prime factorization of A181800(n) (n-th powerful number that is the first integer of its prime signature), in nonincreasing order. 6
2, 3, 4, 5, 2, 2, 6, 3, 2, 7, 4, 2, 3, 3, 8, 5, 2, 4, 3, 9, 6, 2, 5, 3, 2, 2, 2, 10, 7, 2, 4, 4, 6, 3, 3, 2, 2, 11, 8, 2, 5, 4, 7, 3, 4, 2, 2, 12, 9, 2, 6, 4, 3, 3, 2, 8, 3, 5, 2, 2, 5, 5, 13, 10, 2, 7, 4, 4, 3, 2, 9, 3, 6, 2, 2, 6, 5, 14, 11, 2, 8, 4, 5, 3, 2, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

COMMENTS

A212179(n) gives length of row n.

Table represents prime signature (cf. A212171) and second signature (cf. A212172) of A181800.

LINKS

Table of n, a(n) for n=2..87.

Will Nicholes, Prime Signatures

FORMULA

Row n is identical to row A181800(n) of tables A212171 and A212172.

EXAMPLE

Since 72 is a member of A181800, all positive exponents in its prime factorization (2^3*3^2) equal or exceed 2. Therefore, its second signature is the same as its prime signature, namely, {3,2} (nonincreasing version).  Since 72 = A181800 (8), row 8 represents the prime signature and second signature {3,2}.

CROSSREFS

Cf. A181800, A212171, A212172, A212179.

Sequence in context: A037839 A165072 A141404 * A070671 A119281 A328943

Adjacent sequences:  A212173 A212174 A212175 * A212177 A212178 A212179

KEYWORD

nonn,tabf

AUTHOR

Matthew Vandermast, Jun 03 2012

STATUS

approved

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Last modified November 13 12:45 EST 2019. Contains 329094 sequences. (Running on oeis4.)