/* Predicate functions that checks wether an integer is a Blum integer or not */
blum_p(n):=lambda([x],length(ifactors(x))=2 and unique(map(second,ifactors(x)))=[1] and mod(ifactors(x)[1][1],4)=3 and mod(ifactors(x)[2][1],4)=3)(n)$

/* Function that returns a list of the first len Blum integers */
blum_count(len):=block(
    [i:1,count:0,result:[]],
    while count<len do (if blum_p(i) then (result:endcons(i,result),count:count+1),i:i+1),
    result)$

/* Test cases */
/* First 50 Blum integers */
blum_count(50);

/* Blum integer number 26828 */
last(blum_count(26828));