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A270393 Another variant of narcissistic numbers: integers n equal the product of squared digits of n divided by the sum of digits of n, i.e., n = A007954(n)^2/A007953(n). 0
1, 2, 3, 4, 5, 6, 7, 8, 9, 36, 735 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

No other terms below 10^300. - Max Alekseyev, May 31 2018

LINKS

Table of n, a(n) for n=1..11.

EXAMPLE

36 is a term because 36 = (3^2*6^2)/(3+6).

735 is a term because 735 = (7^2*3^2*5^2)/(7+3+5).

MATHEMATICA

Select[Range[10^6], Function[k, k == Apply[Times, #^2]/(Total@ #) &@ IntegerDigits@ k]@ # &] (* Michael De Vlieger, Mar 16 2016 *)

PROG

(PARI) { is_A270393(n) = my(d = digits(n)); n == vecprod(d)^2/vecsum(d); } \\ Michel Marcus, Mar 17 2016

CROSSREFS

Subsequence of A128606.

Cf. A005188, A257554.

Sequence in context: A316147 A080161 A257554 * A257787 A098771 A276810

Adjacent sequences:  A270390 A270391 A270392 * A270394 A270395 A270396

KEYWORD

nonn,more,base

AUTHOR

José de Jesús Camacho Medina, Mar 16 2016

STATUS

approved

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Last modified April 20 06:59 EDT 2021. Contains 343125 sequences. (Running on oeis4.)