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A162840 Numbers k such that the cube of the sum of digits of k equals the product of digits of k. 1
0, 1, 666666, 1377789, 1377798, 1377879, 1377897, 1377978, 1377987, 1378779, 1378797, 1378977, 1379778, 1379787, 1379877, 1387779, 1387797, 1387977, 1389777, 1397778, 1397787, 1397877, 1398777, 1555888, 1558588, 1558858 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Chai Wah Wu, Table of n, a(n) for n = 0..10000

FORMULA

{n: A118880(n)=A007954(n)}. - R. J. Mathar, Jul 19 2009

EXAMPLE

666666 is in the sequence because (1) cubed sum of its digits is (6+6+6+6+6+6)^3 = 46656, (2) the product of its digits is 6*6*6*6*6*6=46656; 46656=46656.

MAPLE

A007953 := proc(n) add(d, d=convert(n, base, 10)) ; end: A007954 := proc(n) mul(d, d=convert(n, base, 10)) ; end: A118880 := proc(n) (A007953(n))^3; end: for n from 1 to 2000000 do if A118880(n) = A007954(n) then printf("%d, \n", n) ; fi; od: # R. J. Mathar, Jul 19 2009

MATHEMATICA

Select[Range[0, 156*10^4], Total[IntegerDigits[#]]^3==Times@@IntegerDigits[#]&] (* Harvey P. Dale, Jul 07 2022 *)

CROSSREFS

Cf. A007954, A118880, A117720, A034710. - R. J. Mathar, Jul 19 2009

Sequence in context: A069373 A270801 A348832 * A233817 A204887 A251503

Adjacent sequences:  A162837 A162838 A162839 * A162841 A162842 A162843

KEYWORD

base,nonn

AUTHOR

Boris Hostnik (megpplus(AT)siol.net), Jul 14 2009

STATUS

approved

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Last modified September 25 18:27 EDT 2022. Contains 356986 sequences. (Running on oeis4.)