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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 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: A080161 A345405 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 December 5 06:35 EST 2022. Contains 358582 sequences. (Running on oeis4.)