Oops, sorry, life-line, mea culpa.
Possibly misfit; as a mathematics natural I remember that one resonating.
But I don't know what they're collected in; I read them in astoundings, analogs, the best whatever of the year. (Oh, all right, I've got "the past through tomorrow volume 2" for some of the future history ones.
What was his psi/witches short?