Recorrência Operações nos Naturais Naturais e Relação de Ordem nos Números Naturais

( )\n( ) ( ) ( ) ( ) { } ( . . . ) ( ) ( ) ( ) ( ) ( ) ( ) ( )\n( )\n( )\n( )\n( )\n( )\n( )\n( )\n( )\n ( )\n( )\n( )\n( )\n( )\n( )\n( )\n \n\n\n ( ) S_n = a_1 + a_2 + ... + a_n\nS_n = a_s + a_(s-1) + ... + a_1\n2S_n = (a_1 + a_n) + (a_2 + a_(n-1)) + ... + (a_(n-1) + a_1)( ) ( ) ( ) ( )\n _______\n ( )\n _______\n ( )\n ( )\n _______\n ( )\n _______\n ( )\n_____\n_____\n ( )\n( )\n(( )) ( ) ( )\n ( )\n( )\n(( )) ( ) ( )\n