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A105993 Near-repunit semiprimes. 1
115, 118, 119, 121, 141, 161, 411, 511, 611, 1011, 1101, 1114, 1115, 1119, 1121, 1141, 1191, 1211, 1411, 1711, 5111, 7111, 9111, 11101, 11114, 11141, 11181, 11611, 11911, 13111, 14111, 17111, 18111, 19111, 31111, 61111, 91111, 110111, 111011, 111101 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

EXAMPLE

a(2)=118 is a term because 118 is a semiprime and all digits are 1 except one.

MATHEMATICA

Select[Sort[Flatten[Table[FromDigits/@Permutations[PadRight[{k}, n, 1]], {n, 3, 6}, {k, Range[0, 9]}]]], PrimeOmega[#]==2&&Length[Union[ IntegerDigits[ #]]]>1&] (* Harvey P. Dale, Jun 13 2020 *)

CROSSREFS

Sequence in context: A101111 A129823 A056035 * A036269 A036462 A020443

Adjacent sequences:  A105990 A105991 A105992 * A105994 A105995 A105996

KEYWORD

base,nonn

AUTHOR

Shyam Sunder Gupta, Apr 29 2005

STATUS

approved

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Last modified January 26 07:39 EST 2021. Contains 340434 sequences. (Running on oeis4.)