CREATE TABLE table_64780 ("Constituency number" TEXT, "Name" TEXT, "Reserved for  (  SC / ST /None ) " TEXT, "District" TEXT, "Number of electorates  ( 2009 ) " FLOAT)

What's the constituency number of the Seoni district and has none reserved?
SELECT "Constituency number" FROM table_64780 WHERE "Reserved for ( SC / ST /None)" = 'none' AND "District" = 'seoni'
SELECT "Constituency number" FROM "table_64780" WHERE "District" = 'seoni' AND "Reserved for ( SC / ST /None)" = 'none'