A063889 - OEIS

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A063889

Composite numbers not divisible by 5 which in base 5 contain their largest proper factor as a substring.

4087, 5083, 5731, 8857, 10841, 11983, 15109, 18631, 27317, 29593, 49883, 52319, 61903, 62317, 65509, 67237, 80371, 87707, 89351, 101971, 108781, 114313, 121801, 129739, 136921, 140033, 143231, 147923, 158497, 167477, 186911, 199841, 202537

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..33.

MATHEMATICA

Do[ If[ !PrimeQ[ n ] && Mod[ n, 5 ] != 0 && StringPosition[ ToString[ FromDigits[ IntegerDigits[ n, 5 ] ] ], ToString[ FromDigits[ IntegerDigits[ Divisors[ n ][ [ -2 ] ], 5 ] ] ] ] != {}, Print[ n ] ], {n, 3, 10^6} ]

CROSSREFS

Sequence in context: A126822 A251005 A256028 * A257824 A024022 A145591

Adjacent sequences: A063886 A063887 A063888 * A063890 A063891 A063892

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Aug 27 2001

STATUS

approved