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Numbers prime to 10, 10's digit is odd and 100's digit is odd.
1

%I #6 May 20 2019 15:04:54

%S 111,113,117,119,131,133,137,139,151,153,157,159,171,173,177,179,191,

%T 193,197,199,311,313,317,319,331,333,337,339,351,353,357,359,371,373,

%U 377,379,391,393,397,399,511,513,517,519,531,533,537,539,551,553,557

%N Numbers prime to 10, 10's digit is odd and 100's digit is odd.

%H Robert Israel, <a href="/A133786/b133786.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n+20)=a(n)+200. - _Robert Israel_, May 20 2019

%p seq(seq(seq(seq(10^3*a+10^2*b+10*c+d, d=[1,3,7,9]),c=1..9,2),b=1..9,2),a=0..1); # _Robert Israel_, May 20 2019

%Y Cf. A045798.

%K easy,nonn,base

%O 1,1

%A _Jonathan Vos Post_, Jan 02 2008