Post It DNA Sequences

Adele is doing research in the field of computational biology this summer. She has a DNA sequence D, which is made of a smaller sequence S concatenated K times, i.e, D = S + S + S + ... (K times). Now, she needs to generate the sequence D using a smaller sequence, T of length M, of which she will make N copies. Doing this she'll get F = T + T + ... (N times). Each DNA sequence can be represented