Isn't A037168 just 2p(n) - 2 or 2(p(n) - 1) ? (In which case it's missing an initial 2?) Al -- Alonso del Arte Author at SmashWords.com<https://www.smashwords.com/profile/view/AlonsoDelarte> Musician at ReverbNation.com <http://www.reverbnation.com/alonsodelarte>