1基础数列类型①常数数列如7,7,7,7,7,7,7,7,……②等差数列如11,14,17,20,23,26,……③等比数列如16,24,36,54,81,……④周期数列如2,5,3,2,5,3,2,5,3,……⑤对称数列如2,5,3,0,3,5,2,……⑥质数数列如2,3,5,7,11,13,17⑦合数数列如4,6,8,9,10,12,14注意:1既不是质数也不是合数1
2200以内质数表2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,179,181,191,193,197,1991
3整除判定能被2整除的数,其末尾数字是2的倍数(即偶数)能被3整除的数,各位数字之和是3的倍数能被5整除的数,其末尾数字是5的倍数(即5、0)能被4整除的数,其末两位数字是4的倍数能被8整除的数,期末三位数字是8的倍数能被9整除的数,各位数字之和是9的倍数能被25整除的数,其末两位数字是25的倍数能被125整除的数,其末三位数字125的倍数1
4经典分解91=7×13111=3×37119=7×17133=7×19117=9×13143=11×13147=7×21153=9×17161=7×23171=9×19187=11×17209=19×111
5常用平方数数字平方1124394165256367498649811010011121121441316914196152251625617289183241936120400214412248423529245762562526676277292878429841309001
6常用立方数数字立方1128327464512562