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%I #13 Apr 25 2015 12:00:16
%S 44,46,49,64,66,69,94,96,99,104,155,215,221,222,225,226,251,255,262,
%T 265,333,334,335,338,339,349,355,358,385,393,394,395,469,515,551,555,
%U 557,558,577,585,587,622,625,655,695,774,777,822,825,826,855,857,862,865
%N Integers that become semiprime when any single digit is removed.
%C The subsequence of semiprimes begins: 46, 49, 69, 94, 155, 215, 221, 226, 262, 265, 334, 335, 339, 355, 358, 393, 394, 395, 469, 515, 551, 622, 655, 695, 862, 865, 914, 933, 934, 951, 955, 1111, 1115, 1119, 1159, 1219, 1411, 1415, 1466, 2021, 2026, 2062, 2095, 2159, 2899, 2959, 2995, 2998, 3035, 3039, ....
%C The subsequence of primes begins: 251, 349, 557, 577, 587, 857, 877, 1559, 1669, 4111, 4973, 5051, 5119, 5519, 5591, 6299, 6679, 6871, 6899, 6949, 7213, 7789, 7949, 7993, 8669, 8699, 9133, 9221, 9551, 9749, ....
%C This is to semiprimes A001358 as A034895 is to primes A000040. Note that this is not a subset of A107342, as there are values with nonsemiprime digits, beginning with 104, 155, 215, 221, 222, ....
%H Harvey P. Dale, <a href="/A178755/b178755.txt">Table of n, a(n) for n = 1..1000</a>
%F a(10) = 104 because deleting the "1" gives "04" which by OEIS protocol becomes the semiprime 4=2*2; deleting the "0" gives the semiprime 14=2*7; and deleting the "4" gives the semiprime 10=2*5.
%t Select[Range[3000],Union[PrimeOmega[FromDigits/@Subsets[IntegerDigits[#],{IntegerLength[#]-1}]]]=={2}&] (* _Harvey P. Dale_, Apr 25 2015 *)
%Y Cf. A001358, A034895, A107342.
%K base,nonn
%O 1,1
%A _Jonathan Vos Post_, Jun 09 2010
%E Extended by _Ray Chandler_
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