I am pretty sure it was him. Maybe it was a bit earlier than 1970, but it can't have been much later, because decimalisation happened not long after. And it is not New Math, which I know well. I am sure he DID appear, apparently live, on one series of David Frost's programmes, and maybe he wrote songs specifically for that. I read that in 1965, he did That Was the Year That Was, (American version) both album and concert.