On the sum of digits of some sequences of integers

Central European Journal of Mathematics - Tập 11 - Trang 188-195 - 2012
Javier Cilleruelo1,2, Florian Luca3, Juanjo Rué1, Ana Zumalacárregui1,2
1Instituto de Ciencias Matemáticas (CSIC-UAM-UC3M-UCM), Madrid, Spain
2Departamento de Matemáticas, Universidad Autónoma de Madrid, Madrid, Spain
3Centro de Ciencias Matemáticas, Universidad Nacional Autónoma de México, Morelia, Michoacán, Mexico

Tóm tắt

Let b ≥ 2 be a fixed positive integer. We show for a wide variety of sequences {a n } =1 ∞ that for almost all n the sum of digits of a n in base b is at least c b log n, where c b is a constant depending on b and on the sequence. Our approach covers several integer sequences arising from number theory and combinatorics.

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