%I A087631
%S A087631 1,6,35,268,2092,17263,146565,1274244,11272025,101053126
%N A087631 Number of n-digit primes == 3 (mod 10). E.g. there exist 6 two-digit
prime numbers(13,23,43,53,73,83) with unit's place 3.
%e A087631 E.g. a(3)=35, since there are 35 three-digit numbers with unit place
digit as 3.
%o A087631 (JAVA) The terms of the sequences are generated by changing the range
for j for the various number of digits. E.g. it ranges from 100 to
999 for three-digit numbers. float r,x; int c=0,count=0; for (float
j=100f; j<1000f; j++) { for (float i=2f; i<j; i++) { r=j%i; if (r==0)
c=1; } if (c == 0) { x=j%10; if (x==3) count=count+1; } c=0; } System.out.println("count
= "+count);
%Y A087631 Sequence in context: A000399 A081051 A145145 this_sequence A167579 A030446
A093989
%Y A087631 Adjacent sequences: A087628 A087629 A087630 this_sequence A087632 A087633
A087634
%K A087631 nonn
%O A087631 0,2
%A A087631 Meenakshi Srikanth and Amarnath Murthy (menakan_s(AT)yahoo.com), Sep
15 2003
%E A087631 More terms from Ray Chandler (rayjchandler(AT)sbcglobal.net), Oct 04
2003
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