src/HOL/Library/ASeries.thy
changeset 19279 48b527d0331b
parent 19109 9804aa8d5756
equal deleted inserted replaced
19278:4d762b77d319 19279:48b527d0331b
    71     "(\<Sum>i\<in>{..<n}. a+?I i*d) =
    71     "(\<Sum>i\<in>{..<n}. a+?I i*d) =
    72      ((\<Sum>i\<in>{..<n}. a) + (\<Sum>i\<in>{..<n}. ?I i*d))"
    72      ((\<Sum>i\<in>{..<n}. a) + (\<Sum>i\<in>{..<n}. ?I i*d))"
    73     by (rule setsum_addf)
    73     by (rule setsum_addf)
    74   also from ngt1 have "\<dots> = ?n*a + (\<Sum>i\<in>{..<n}. ?I i*d)" by simp
    74   also from ngt1 have "\<dots> = ?n*a + (\<Sum>i\<in>{..<n}. ?I i*d)" by simp
    75   also from ngt1 have "\<dots> = (?n*a + d*(\<Sum>i\<in>{1..<n}. ?I i))"
    75   also from ngt1 have "\<dots> = (?n*a + d*(\<Sum>i\<in>{1..<n}. ?I i))"
    76     by (simp add: setsum_mult setsum_head_upt)
    76     by (simp add: setsum_right_distrib setsum_head_upt)
    77   also have "(1+1)*\<dots> = (1+1)*?n*a + d*(1+1)*(\<Sum>i\<in>{1..<n}. ?I i)"
    77   also have "(1+1)*\<dots> = (1+1)*?n*a + d*(1+1)*(\<Sum>i\<in>{1..<n}. ?I i)"
    78     by simp
    78     by simp
    79   also from ngt1 have "{1..<n} = {1..n - 1}"
    79   also from ngt1 have "{1..<n} = {1..n - 1}"
    80     by (cases n) (auto simp: atLeastLessThanSuc_atLeastAtMost)    
    80     by (cases n) (auto simp: atLeastLessThanSuc_atLeastAtMost)    
    81   also from ngt1 
    81   also from ngt1