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A233455 Numbers n such that n^9 starts with n itself (in base 10). 7
0, 1, 10, 75, 100, 750, 1000, 4217, 7499, 10000, 100000, 177828, 1000000, 10000000, 74989421, 100000000, 1000000000, 5623413252, 10000000000, 100000000000, 177827941004, 1000000000000, 1778279410039, 10000000000000, 56234132519035, 100000000000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..26.

G. L. Honaker, Jr. and Chris Caldwell, Prime Curios! 7499

EXAMPLE

750^9 = 75084686279296875000000000 begins with 750, so 750 is in the sequence.

MATHEMATICA

Select[Range@ 1000000, Take[IntegerDigits[#^9], IntegerLength@ #] == IntegerDigits@ # &] (* Michael De Vlieger, Aug 31 2015 *)

PROG

(PARI) r=112; print1(1, ", "); e=9; for(n=2, r, p=round((10^(1/(e-1)))^n); f=p^e; b=10^(#Str(f)-#Str(p)); if((f-lift(Mod(f, b)))/b==p, print1(p, ", ")));

CROSSREFS

Cf. A052210, A052211, A233451, A233452, A233453, A233454, A233456.

Sequence in context: A119167 A233100 A266674 * A027778 A026969 A026979

Adjacent sequences:  A233452 A233453 A233454 * A233456 A233457 A233458

KEYWORD

nonn,base,easy

AUTHOR

Arkadiusz Wesolowski, Dec 10 2013

STATUS

approved

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Last modified April 19 11:08 EDT 2019. Contains 322260 sequences. (Running on oeis4.)