The integers $ a_n=\sum_{k=0}^n{\binom nk}^2{\binom{n+k}k}^2, n=0,1,2,... $ appear as denominators of rational approximations to $\zeta(3)=\sum_{k=1}^\infty k^{-3}$ in Apery's proof of the irrationality of $\zeta(3)$. The sequence satisfies a polynomial recursion, namely, $ (n+1)^3a_{n+1}-(2n+1)(17n^2+17n+5)a_n+n^3a_{n-1}=0$, where $n=0,1,2,...$, and admits several curious congruence properties. ... Site design by Paul Zinn-Justin (2005) ...

. The following general subroutines belong to the category IMAGE-IO: . ``Reading/writing of set data'' In parentheses the name of the source file is given. AXPROPS . Return structure with axis properties for a set. ( axprops.c ) . GDSI_CANCEL . Cancels a transfer started with GDSI_READ or GDSI_WRITE. ( gdsi_read.c ) . GDSI_READ . Reads data from (part of) a set. ( gdsi_read.c ) . GDSI_WRITE . Writes data to (part of) an set. ( gdsi_read.c ) .

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. ОГЛАВЛЕНИЕ . Предисловие к четвертому изданию . Введение . § 1. Предмет и задачи астрономии . § 2. Подразделение астрономии . § 3. Возникновение и основные этапы развития астрономии . § 4. Практическое и идеологическое значение астрономии . § 5. Основа и источник астрономических исследований . § 6. Краткий очерк строения Вселенной . Глава I . Основные сведения из сферической астрономии . § 7. Видимые положения светил. Созвездия . § 8. Видимые движения звезд, Солнца, Луны и планет . § 9. Географические