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A281745 Numbers k with the property that the square root of the product of the digits of k is equal to the sum of the square roots of its digits. 1
1, 2, 3, 4, 5, 6, 7, 8, 9, 44, 149, 194, 228, 282, 333, 419, 491, 822, 914, 941, 11199, 11444, 11919, 11991, 14144, 14414, 14441, 19119, 19191, 19911, 41144, 41414, 41441, 44114, 44141, 44411, 91119, 91191, 91911, 99111, 11111449, 11111494, 11111944, 11114149 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..10000

EXAMPLE

1 is a term because sqrt(1) = sqrt(1);

44 is a term because sqrt(4*4) = sqrt(4) + sqrt(4);

941 is a term because sqrt(9*4*1) = sqrt(9) + sqrt(4) + sqrt(1).

MATHEMATICA

Select[Range[10^6], Sqrt[Times @@ #] == Total[Sqrt@ #] &@ IntegerDigits@ # &] (* Michael De Vlieger, Feb 02 2017 *)

PROG

(PARI) isok(n) = my(d = vecsort(digits(n))); sqrt(prod(k=1, #d, d[k])) == sum(k=1, #d, sqrt(d[k])); \\ Michel Marcus, Jan 29 2017

CROSSREFS

Cf. A007953, A007954, A034710.

Sequence in context: A342442 A342755 A129513 * A302501 A183532 A257829

Adjacent sequences: A281742 A281743 A281744 * A281746 A281747 A281748

KEYWORD

nonn,base

AUTHOR

José de Jesús Camacho Medina, Jan 28 2017

EXTENSIONS

More terms from Jon E. Schoenfield, Jan 30 2017

STATUS

approved

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Last modified January 30 12:01 EST 2023. Contains 359943 sequences. (Running on oeis4.)