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A158989 Numbers n such that product of double factorials of the digits of n equals sigma(n). 0
1, 54, 62, 4190, 4920, 10538, 12376, 16065, 16732, 26345, 37236, 47026, 48323, 53480, 56712, 58520, 61209, 62337, 65163, 83720, 84135, 94520, 100980, 126238, 135266, 141078, 143726, 146910, 147354, 154238, 174217, 183505, 185334, 207328 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..34.

EXAMPLE

sigma(444119)=4!!*4!!*4!!*1!!*1!!*9!!, so 444119 is in the sequence.

MATHEMATICA

Select[Range[210000], DivisorSigma[1, # ]==Apply[Times, IntegerDigits[ # ]!! ]&]

CROSSREFS

Cf. A137603, A158990, A158991, A158992.

Sequence in context: A095511 A095501 A318235 * A088489 A025331 A025323

Adjacent sequences:  A158986 A158987 A158988 * A158990 A158991 A158992

KEYWORD

base,easy,nonn

AUTHOR

Farideh Firoozbakht, Jul 07 2009

STATUS

approved

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Last modified June 20 09:12 EDT 2019. Contains 324234 sequences. (Running on oeis4.)