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A032746
Super-6 Numbers (6 * n^6 contains substring '666666' in its decimal expansion).
2
27257, 272570, 302693, 323576, 364509, 502785, 513675, 537771, 676657, 678146, 731378, 831122, 836553, 913797, 920456, 921269, 1045361, 1144983, 1169054, 1283069, 1288697, 1292673, 1343642, 1346117, 1472078, 1523993, 1640026
OFFSET
1,1
COMMENTS
The terms a({5, 9, 11, 12}) = {364509, 676657, 731378, 831122} are such that 6*a(n)^6 == 66666646, 66666694, or 66666624 (mod 10^8). Therefore, any number congruent to one of these (mod 5*10^7) is also in the sequence. Of course, for any term a(n), all numbers a(n)*10^k, k >= 0, are also in the sequence. - M. F. Hasler, Jul 16 2024
REFERENCES
C. A. Pickover, "Keys to Infinity", New York: Wiley, p. 7, 1995.
LINKS
Giovanni Resta, super-d numbers, personal web site "Numbers Aplenty", 2013
Eric Weisstein's World of Mathematics, Super-d Number.
MATHEMATICA
With[{c=6}, Select[Range[165*10^4], SequenceCount[IntegerDigits[c #^c], PadRight[ {}, c, c]]>0&]] (* Harvey P. Dale, Jan 18 2023 *)
PROG
(PARI) select( {is_A032746(n)=is_A014569(n, 6)}, [1..10^5])
for(n=1, oo, is_A032746(n)&& print1(n", ")) \\ Quite slow... - M. F. Hasler, Jul 16 2024
CROSSREFS
Cf. A014569 (d=3), A032743 - A032749 (d=2, ..., 9).
Sequence in context: A250852 A157820 A251777 * A099230 A267706 A237381
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, May 15 1998
EXTENSIONS
Offset changed to 1 by M. F. Hasler, Jul 16 2024
STATUS
approved