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A032549
Numbers that, when expressed in base 7 and then interpreted in base 10, yield a multiple of the original number.
5
1, 2, 3, 4, 5, 6, 51, 102, 105, 153, 156, 207, 210, 258, 261, 312, 315, 2589, 2590, 2601, 2753, 5354, 5355, 5506, 8108, 8259, 8260, 10861, 11013, 11025, 13614, 13615, 13626, 13766, 13778, 16379, 16380, 16531, 33045, 140403, 289065, 1123224
OFFSET
1,2
COMMENTS
Decimal 'base-7 looking' numbers divided by their actual base-7 values (n) is an integer.
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..70 (terms < 10^12, first 63 terms from Paolo P. Lava)
MATHEMATICA
Select[Range@ 300000, Mod[ FromDigits[ IntegerDigits[#, 7]], #] == 0 &] (* Giovanni Resta, Oct 21 2019 *)
CROSSREFS
Cf. A032548, A032550. See also A032532 for explanation.
Sequence in context: A044908 A024642 A062944 * A028428 A273473 A278941
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Apr 15 1998
EXTENSIONS
Offset set to 1 by Giovanni Resta, Oct 21 2019
Name edited by Jon E. Schoenfield, Oct 25 2019
STATUS
approved