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A227801 Numbers n whose sum of digits, sum of square of digits and sum of cube of digits all have the same digital root. 0
1, 9, 10, 11, 19, 36, 47, 63, 74, 90, 91, 99, 100, 101, 109, 110, 111, 119, 136, 147, 163, 174, 190, 191, 199, 306, 316, 333, 360, 361, 369, 396, 407, 417, 444, 470, 471, 479, 497, 603, 613, 630, 631, 639, 666, 693, 704, 714, 740, 741, 749, 777, 794, 900, 901, 909, 910, 911, 919, 936, 947, 963, 974, 990, 991, 999, 1000, 1001 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..68.

EXAMPLE

a(6)=36 since (first power) 3+6=9; (second power) 3^2+6^2=9+36=45 and 4+5=9; (third power) 3^3+6^3=27+216=243 and 2+4+3=9.

PROG

(PARI) dr(n) = if (n, (n-1)%9+1); \\ from A010888

dsq(n) = if (n, d = digits(n); sum(id = 1, #d, d[id]^2));

dcb(n) = if (n, d = digits(n); sum(id = 1, #d, d[id]^3));

ok(n) = (dr(n) == dr(dcb(n))) && (dr(n) == dr(dsq(n))); \\ Michel Marcus, Sep 24 2013

CROSSREFS

Cf. A010888 (digital root of n), A007953, A003132, A055012.

Sequence in context: A168042 A045522 A054967 * A048031 A048013 A048048

Adjacent sequences:  A227798 A227799 A227800 * A227802 A227803 A227804

KEYWORD

nonn,base

AUTHOR

Carmine Suriano, Sep 23 2013

EXTENSIONS

Title improved by Peter Bala, Sep 25 2013

STATUS

approved

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Last modified April 23 03:26 EDT 2019. Contains 322380 sequences. (Running on oeis4.)