|
%I #7 Dec 05 2013 19:55:13
%S 2,23,41,821,4409,2063,224401,8609,20066003,20628046223,82260284069,
%T 2248462002229,224682444608243
%N Start of first occurrence of just n consecutive primes with all even digits except the least significant digit.
%C If the least significant digit must be odd, then a(1) = 241.
%C a(14) > 2*10^15. [From _Donovan Johnson_, Sep 21 2010]
%e a(8) = 8609: the 8 consecutive primes are 8609, 8623, 8627, 8629, 8641, 8647, 8663, 8669.
%t a = {0, 1, 1, 1}; Do[ If[ Union[ EvenQ[ Drop[ IntegerDigits[ Prime[n]], -1]]] == {True}, a = Append[a, 1], a = Append[a, 0]], {n, 5, 10^5}]; Do[k = 3; b = Table[1, {n}]; b = Insert[b, 0, {{1}, {-1}}]; While[k < 10^5 - n && Take[a, {k - 1, k + n}] != b, k++ ]; If[k < 10^5, Print[ Prime[k]], Print[0]], {n, 1, 8}]
%K more,nonn,base
%O 1,1
%A _Amarnath Murthy_, Mar 09 2002
%E Edited and extended by _Robert G. Wilson v_, Apr 10 2002
%E a(9)-a(12) from _Donovan Johnson_, Sep 03 2008
%E a(13) from _Donovan Johnson_, Sep 21 2010
|
