This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
Silvester Resnik has authored 5 sequences.
fibomod(n, m) = lift(Mod([0, 1; 1, 1], m)^(n+1))[1, 1]; isok(n) = prod(k=0, 8, fibomod(n, n+k)==0);
a(1) = 9 since it is the first occurrence of a single odd semiprime; a(2) = 15 since 15 is the first of two consecutive odd semiprimes in the sequence of semiprimes; a(3) = 87 since 87 is the first of exactly three consecutive odd semiprimes; a(4) = 49 since 49 is the first of exactly four consecutive odd semiprimes; etc.
SplitBy[ Select[ Range@ 100, PrimeOmega@# == 2 &], Mod[#, 2] &] (* to view the runs of semiprimes of the same parity *)
a(1) = 22 since it is the first occurrence of a single even semiprime; a(2) = 4 since 4 is the first of two consecutive even semiprimes in the sequence of semiprimes; a(3) = 454 since it is the first of three consecutive even semiprimes in the sequence of semiprimes; etc.
SplitBy[ Select[ Range@ 100, PrimeOmega@# == 2 &], Mod[#, 2] &] (* to view the runs of semiprimes of the same parity *)
a(1) = 4 since it is the first occurrence of a semiprime that is not part of a run of two or more semiprimes; a(2) = 14 since it is the first of a run of exactly two consecutive semiprimes of alternating parity; a(3) = 6 since 6 is the first of a run of exactly three consecutive semiprimes of alternating parity; etc.
Table[ SelectFirst[ Split[ Select[ Range@ 10000000, PrimeOmega@# == 2 &], Mod[#1, 2] != Mod[#2, 2] &], Length@# == n &][[1]], {n, 13}]
fibomod(n, m) = lift(Mod([0, 1; 1, 1], m)^(n+1))[1, 1]; isok(n) = prod(k=0, 7, fibomod(n, n+k)==0);
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