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A105983 Near-repdigit semiprimes with 2 as repeated digit. 1
122, 202, 221, 226, 262, 422, 622, 922, 2122, 2227, 2229, 2722, 4222, 8222, 20222, 22223, 22226, 22262, 22322, 22522, 22622, 22822, 25222, 32222, 52222, 202222, 222221, 222223, 222242, 222422, 223222, 224222, 226222, 262222, 272222, 622222 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..100

EXAMPLE

a(2)=202 is a term because 202 is a semiprime and all digits are equal to 2 except one.

MATHEMATICA

Rest[Select[FromDigits/@Flatten[Permutations/@Flatten[ Table[PadRight[ {n}, k, 2], {k, 3, 6}, {n, 0, 9}], 1], 1], PrimeOmega[#]==2&]]//Sort (* Harvey P. Dale, Jun 11 2018 *)

CROSSREFS

Sequence in context: A224599 A207147 A222578 * A099154 A304605 A158131

Adjacent sequences:  A105980 A105981 A105982 * A105984 A105985 A105986

KEYWORD

base,nonn

AUTHOR

Shyam Sunder Gupta, Apr 29 2005

STATUS

approved

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Last modified November 16 17:25 EST 2019. Contains 329201 sequences. (Running on oeis4.)