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A091081 Numbers n which when converted to base 7, reversed and converted back to base 10 yield a number m such that n mod m = 0. Cases which are trivial or result in digit loss are excluded. 6
36, 288, 1800, 2052, 2304, 12384, 14400, 16416, 86472, 88236, 99072, 100836, 115200, 605088, 619200, 691776, 705888, 806688, 4235400, 4247748, 4323600, 4335948, 4840704, 4853052, 4928904, 4941252, 5534208, 5647104, 29647584, 29746368, 30254400, 30353184 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Trivial cases are those numbers which upon conversion result in a number which is palindromic (m = reverse(m)), or a palindrome plus trailing zeros such that m = reverse(m)*10^z where z=number of lost zeros. Nontrivial digit loss occurs when a converted number has trailing zeros that drop off when the number is reversed.

LINKS

Table of n, a(n) for n=1..32.

C. Seggelin, Numbers Divisible by Digit Permutations. [Broken link]

EXAMPLE

a(1) = 36 because: 36 in base 7 is 51; 51 reversed is 15; 15 converted back to base 10 is 12 and 36 mod 12 = 0.

PROG

(PARI) /* See A091077 and use PARI script with b=7 */

CROSSREFS

Cf. A091077 (same in base 3), A091078 (base 4), A091079 (base 5), A091080 (base 6), A091082 (base 8), A091083 (base 9), A031877 (base 10).

Sequence in context: A014136 A245435 A288963 * A017462 A226836 A218647

Adjacent sequences:  A091078 A091079 A091080 * A091082 A091083 A091084

KEYWORD

base,nonn

AUTHOR

Chuck Seggelin (barkeep(AT)plastereddragon.com), Dec 18 2003

EXTENSIONS

More terms from Michel Marcus, Oct 10 2014

STATUS

approved

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Last modified February 21 05:23 EST 2020. Contains 332086 sequences. (Running on oeis4.)