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A050322 Number of factorizations indexed by prime signatures: A001055(A025487). 6
1, 1, 2, 2, 3, 4, 5, 7, 5, 7, 9, 12, 11, 11, 16, 19, 21, 15, 29, 26, 30, 15, 31, 38, 22, 47, 52, 45, 36, 57, 64, 30, 77, 98, 67, 74, 97, 66, 105, 42, 109, 118, 92, 109, 171, 97, 141, 162, 137, 165, 56, 212, 181, 52, 198, 189, 289, 139, 250, 257, 269, 254, 77, 382, 267 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

For A025487(m) = 2^k = A000079(k), we have a(m) = A000041(k).

Is a(k) = A000110(k) for A025487(m) = A002110(k)?

LINKS

R. J. Mathar and Michael De Vlieger, Table of n, a(n) for n = 1..5000 (First 300 terms from R. J. Mathar)

MAPLE

A050322 := proc(n)

    A001055(A025487(n)) ;

end proc: # R. J. Mathar, May 25 2017

MATHEMATICA

c[1, r_] := c[1, r] = 1; c[n_, r_] := c[n, r] = Module[{d, i}, d = Select[Divisors[n], 1 < # <= r &]; Sum[c[n/d[[i]], d[[i]]], {i, 1, Length[d]}]]; Map[c[#, #] &, Union@ Table[Times @@ MapIndexed[If[n == 1, 1, Prime[First@ #2]]^#1 &, Sort[FactorInteger[n][[All, -1]], Greater]], {n, Product[Prime@ i, {i, 6}]}]] (* Michael De Vlieger, Jul 10 2017, after Dean Hickerson at A001055 *)

CROSSREFS

Cf. A000041, A000079, A000110, A001055, A002110, A025487.

Sequence in context: A036072 A045475 A082543 * A211858 A029012 A095699

Adjacent sequences:  A050319 A050320 A050321 * A050323 A050324 A050325

KEYWORD

nonn

AUTHOR

Christian G. Bower, Oct 15 1999

STATUS

approved

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Last modified August 24 00:29 EDT 2017. Contains 291052 sequences.