The infinite sum 1?+4 / 7+?9 / 7²+?16 / 7³ ? 25 / 7⁴ ? .... equals

What is the sum of ‘n’ terms in the series: logn? log?(m² / n??) + log?(m³ / n²) + ?log(?m⁴ / n³)

In a number system the product of 44 and 11 is 2124. The number 3111 of this system, when converted to the decimal number system,

becomes: