SAN FRANCISCO — On April 19, 1965, just over 50 years ago, Gordon Moore, then the head of research for Fairchild Semiconductor and later one of the co-founders of Intel, was asked by Electronics Magazine to submit an article predicting what was going to happen to integrated circuits, the heart of computing, in the next 10 years. Studying the trend he’d seen in the previous few years, Moore predicted that every year we’d double the number of transistors that could fit on a single chip of silicon so you’d get twice as much computing power for only slightly more money. When that came true, in 1975, he modified his prediction to a doubling roughly every two years. “Moore’s Law” has essentially held up ever since — and, despite the skeptics, keeps chugging along, making it probably the most remarkable example ever of sustained exponential growth of a technology.