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A278937
Numbers k such that 3 is the largest decimal digit of k^3.
8
11, 101, 110, 1001, 1010, 1100, 10001, 10010, 10100, 11000, 100001, 100010, 100100, 101000, 110000, 684917, 1000001, 1000010, 1000100, 1001000, 1010000, 1100000, 6849170, 10000001, 10000010, 10000100, 10001000, 10010000, 10100000, 11000000
OFFSET
1,1
COMMENTS
A038444 is a subsequence. Are there an infinite number of terms not in A038444 that are not a multiple of 10? - Chai Wah Wu, Dec 02 2016
Conjecture: sequence is equal to A038444 plus terms of the form 684917*10^k for k >= 0. - Chai Wah Wu, Sep 02 2017
Conjecture is true up to 4.8*10^18. - Giovanni Resta, Sep 03 2017
LINKS
FORMULA
a(n)^3 = A278936(n).
EXAMPLE
684917 is in the sequence because 684917^3 = 321302302131323213.
PROG
(PARI) select(n->vecmax(digits(n^3))==3, vector(1000000, n, n))
(Magma) [n: n in [1..2*10^7] | Max(Intseq(n^3)) eq 3]; // Vincenzo Librandi, Dec 03 2016
CROSSREFS
Cf. A000578 (the cubes: n^3), A038444, A277960 (analog for squares), A278936 (cubes of the terms: a(n)^3).
Sequence in context: A239236 A043494 A277959 * A038444 A115824 A364326
KEYWORD
nonn,base
AUTHOR
Colin Barker, Dec 02 2016
STATUS
approved