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%I #3 Mar 30 2012 18:40:52
%S 41,61,79,101,149,151,211,223,251,263,331,347,353,383,397,461,491,751,
%T 1553,1571,1583,1621,1657,1669,1741,1777,1823,2851,2861,2879,2917,
%U 2939,3943,4951,10601,11113,11159,11801,11903,12101,12203,12301,12907,13309
%N Smallest prime number > a(n-1) that contains the n-th semiprime number as a substring.
%C Not to be confused with smallest semiprime number > a(n-1) that contains the n-th prime number as a substring. This is the 2nd row of an infinite array A[k,n] = Smallest k-almost prime number > a(n-1) that contains the n-th prime number as a substring. This is one plane of the infinite 3-D array A[j,k,n] = Smallest k-almost prime number > a(n-1) that contains the n-th prime number as a substring in base j representation.
%F a(n) = MIN{p > a(n-1) in A000040 such that A001358(n) as a string of decimal digits is a substring of p as a string of decimal digits}.
%e a(1) = 41 because 41 is the smallest prime whose decimal representation has "4" as a substring, and 4 = 2*2 is the 1st (smallest) semiprime (number of the form p*q where p and q are primes, not necessarily distinct).
%e a(2) = 61 because 61 is the smallest prime whose decimal representation has "6" as a substring, and 6 = 2*3 is the 2nd semiprime.
%e a(3) = 79 because 79 is the smallest prime > 61 whose decimal representation has "9" as a substring, and 9 = 3*3 is the 3rd semiprime.
%Y Cf. A000040, A001358, A144565, A169798.
%K nonn,base,less
%O 1,1
%A _Jonathan Vos Post_, May 18 2010
%E Edited, corrected and extended by _Ray Chandler_, May 23 2010
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