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A212178 Number of exponents >= 2 in canonical prime factorization of A025487(n) (first integer of each prime signature). 1
0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 2, 1, 1, 1, 2, 1, 1, 1, 2, 2, 1, 0, 2, 1, 1, 2, 2, 1, 1, 2, 1, 1, 2, 2, 1, 1, 2, 3, 1, 1, 2, 2, 2, 2, 2, 1, 1, 2, 3, 1, 1, 2, 2, 0, 2, 2, 2, 1, 1, 2, 3, 1, 1, 2, 2, 1, 2, 2, 3, 2, 1, 3, 2, 1, 2, 3, 2, 1, 2, 1, 2, 2, 1, 2, 2, 3, 2, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,11

COMMENTS

Length of row n of A212175 equals a(n) if a(n) is positive, 1 otherwise.

LINKS

Table of n, a(n) for n=1..88.

Will Nicholes, Prime Signatures

FORMULA

a(n) = A056170(A025487(n)).

EXAMPLE

The canonical prime factorization of 24 (2^3*3) has 1 exponent that equals or exceeds 2. Since 24 = A025487(8), a(8) = 1.

CROSSREFS

Cf. A025487, A212172.

Sequence in context: A086257 A161098 A136177 * A322818 A327500 A066922

Adjacent sequences:  A212175 A212176 A212177 * A212179 A212180 A212181

KEYWORD

nonn,tabf

AUTHOR

Matthew Vandermast, Jun 04 2012

STATUS

approved

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Last modified November 17 18:24 EST 2019. Contains 329241 sequences. (Running on oeis4.)