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%I #22 Nov 12 2019 12:50:18
%S 403,1003,110203,118003,418307,429491,439097,559003,1239869,1887239,
%T 2481463,2502977,3381403,3693419,5646257,6120403,6586003,6954767,
%U 7042661,8350003,11305093,13083403,13760203,17297519,21159419
%N Lesser of a pair (x,y) of consecutive terms of A045572 (numbers coprime to 2*5), both semiprimes and such that the prime factors of x are adjacent primes to the factors of y.
%C Within the subset A045572 of numbers ending in 1, 3, 7 or 9, i.e., excluding numbers having 2 or 5 as prime factor, we look for two consecutive elements (x,y) which are both semiprimes and whose prime factors are "adjacent" primes, i.e., if x=p(i)*p(j), then we require y=p(i +/- 1)*p(j +/- 1).
%H Woodhodgson, <a href="http://groups.yahoo.com/group/primenumbers/message/24261">Adjacent composite numbers with pairs of adjacent prime factors</a>, Primenumbers Group, Jun 15 2012.
%H Woodhodgson, Maximilian Hasler, <a href="/A213605/a213605.txt">Adjacent composite numbers with pairs of adjacent prime factors</a>, digest of 2 messages in primenumbers Yahoo group, Jun 14 - Jun 15, 2012.
%e a(1) = 403 because (403,407) are such that 403=13*31 and 407=11*37, (11,13) and (31,37) being consecutive primes.
%e a(2) = 1003 because (1003,1007) are such that 1003=17*59 and 1007=19*53, where (17,19) and (53,59) are pairs of subsequent primes.
%Y Cf. A213606 (the greater ("y") of the pair of semiprimes).
%K nonn
%O 1,1
%A _M. F. Hasler_, Jun 15 2012
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