A237433 Canonical index of prime signature of n.

1, 2, 2, 3, 2, 4, 2, 5, 3, 4, 2, 6, 2, 4, 4, 8, 2, 4, 2, 6, 4, 4, 2, 9, 3, 4, 5, 6, 2, 7, 2, 13, 4, 4, 4, 10, 2, 4, 4, 9, 2, 7, 2, 6, 6, 4, 2, 14, 3, 4, 4, 6, 2, 7, 4, 9, 4, 4, 2, 11, 2, 4, 6, 20, 4, 7, 2, 6, 4, 7, 2, 15, 2, 4, 4, 6, 4, 7, 2, 14, 8, 4, 2, 11, 4, 4, 4, 9, 2, 7, 4, 6, 4, 4, 4, 21, 2, 4, 6, 10

Offset

1,2

Comments

Index of prime signature of n when prime signatures are listed in "canonical" order as defined in the "Canonical ordering of the partitions" link.

Note that A236515 uses a different ordering (see 2nd link).

Links

Table of n, a(n) for n=1..100.

OEIS Wiki, Canonical ordering of the partitions

OEIS Wiki, Orderings of prime signature

Example

a(7) = a({1}) = 2, a(180) = a({2,2,1}) = 17, a(216) = a({3,3}) = 24
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a(1) = 1,
For all n in A000040, prime_signature(n) = {1}, a(n) = 2,
For all n in A001248, prime_signature(n) = {2}, a(n) = 3,
For all n in A006881, prime_signature(n) = {1,1}, a(n) = 4,
For all n in A030078, prime_signature(n) = {3}, a(n) = 5,
For all n in A054753, prime_signature(n) = {2,1}, a(n) = 6,
For all n in A007304, prime_signature(n) = {1,1,1}, a(n) = 7, etc.

Crossrefs

Cf. A236515.

Sequence in context: A290110 A300250 A319357 * A236515 A318469 A300224

Adjacent sequences: A237430 A237431 A237432 * A237434 A237435 A237436

Keyword

nonn

Author

Sung-Hyuk Cha, Feb 07 2014

Status

approved