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 A270537 Numbers that are equal to their number of digits multiplied by the sum the cubes of the digits. 0
 1, 2080, 2376, 2580, 3784 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS EXAMPLE 2080 is a term because 2080 = 4 * (2^3 + 0^3 + 8^3 + 0^3); 2376 is a term because 2376 = 4 * (2^3 + 3^3 + 7^3 + 6^3). MATHEMATICA Position[ Table[ IntegerLength[ k] Sum[( Floor[k/10^n] - 10 Floor[k/10^(n + 1)])^3, {n, 0, IntegerLength@ k}] - k, {k, 1, 10^6}], 0] Select[Range[10^5], With[{id=IntegerDigits[#]}, #==Length[id]*Plus@@(id^3)]&] (* Ray Chandler, Apr 01 2016 *) PROG (PARI) isok(n) = my(d=digits(n)); n == #d*sum(k=1, #d, d[k]^3); \\ Michel Marcus, Mar 25 2016 CROSSREFS Sequence in context: A076425 A249654 A180921 * A076581 A183675 A178272 Adjacent sequences:  A270534 A270535 A270536 * A270538 A270539 A270540 KEYWORD nonn,base,fini,full AUTHOR José de Jesús Camacho Medina, Mar 18 2016 STATUS approved

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Last modified June 28 12:00 EDT 2022. Contains 354907 sequences. (Running on oeis4.)