D:\sbornik\...\Said_9\tpel.DVI Mathematical Problems of Computer Science 35, 63{69, 2011. I r r educible Compositions of P olynomials Over Finite Fields of E ven Char acter istic¤ S a e id M. Me h r a b i a n d Me ls ik K . K yu r e g ya n Institue for Informatics and Automation Problems of NAS of RA e-mail smbatt@ipia.sci.am Abstract This note presents some results with the constructive theory of synthesis of irre- ducible polynomials over a Galois ¯eld with even characteristic. We prove a theorem that plays an important role for constructing irreducible polynomials. By this theo- rem a recurrent method for constructing families of irreducible polynomials of degree n2k (k = 1; 2; :::) over F2s is proposed. Refer ences [1 ] E .R . B e r le ka m p , A lg e b r a ic Co d in g Th e o r y, Mc Gr a w-H ill, N e w Y o r k, 1 9 6 8 . [2 ] I.F. 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K yu r e g ya n ,\ R e c u r r e n t m e t h o d s fo r c o n s t r u c t in g ir r e d u c ib le p o lyn o m ia ls o ve r Fq o f o d d c h a r a c t e r is t ic s " , F inite F ields Appl, vo l. 9 , p p . 3 9 -5 8 , 2 0 0 3 . ¤2000 Mathematics subject classi¯cations: 47A68, 47A70 6 3 6 4 Irreducible Compositions of Polynomials Over Finite Fields of Even Characteristic [1 3 ] M. K . K yu r e g ya n , \ R e c u r r e n t m e t h o d s fo r c o n s t r u c t in g ir r e d u c ib le p o lyn o m ia ls o ve r Fq o f o d d c h a r a c t e r is t ic s II" , F inite F ields Appl, vo l. 1 2 , p p . 3 5 7 -3 7 8 , 2 0 0 6 . [1 4 ] M.K . K yu r e g ya n , \ Qu a d r a t ic t r a n s fo r m a t io n s a n d s yn t h e s is o f ir r e d u c ib le p o lyn o m i- a ls o ve r ¯ n it e ¯ e ld s " , D okl, Akad, Nauk Arm, SSR , vo l. 8 4 ( 2 ) , p p . 6 7 -7 1 , 1 9 8 7 . ( in R u s s ia n ) . 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Me yn ,\ E xp lic it N -p o lyn o m ia ls o f 2 -p o we r d e g r e e o ve r ¯ n it e ¯ e ld s " , D esigns Codes Cryptogr, vo l. 6 , p p . 1 0 7 -1 1 6 , 1 9 9 5 . [2 1 ] S . P e r lis , \ N o r m a l b a s e s o f c yc lic ¯ e ld s o f p r im e -p o we r d e g r e e " ,D uke M ath. J ., vo l. 9 , p p . 5 0 7 -5 1 7 , 1 9 4 2 . [2 2 ] J.V o n z u r Ga t h e n , E . K a lt o fe n ,\ Fa c t o r iz a t io n o f m u lt iva r ia t e p o lyn o m ia ls o ve r ¯ n it e ¯ e ld s " , M ath.Comput, vo l.4 5 , p p . 2 5 1 -2 6 1 , 1 9 8 5 . [2 3 ] R . R . V a r s h a m o v,\ A g e n e r a l m e t h o d o f s yn t h e s iz in g ir r e d u c ib le p o lyn o m ia ls o ve r Ga lo is ¯ e ld s " , Soviet M ath. D okl, vo l. 2 9 , p p . 3 3 4 - 3 3 6 , 1 9 8 4 . ¼áõÛ· µÝáõó·ñÇãáí ãµ»ñíáÕ µ³½Ù³Ý¹³ÙÝ»ñÇ µ³Õ³¹ñáõÃÛáõÝÝ»ñ í»ñç³íáñ ¹³ßï»ñÇ íñ³ ê. Ø»Ññ³µÇ ¨ Ø. ÎÛáõñ»ÕÛ³Ý ²Ù÷á÷áõÙ ²Ûë ³ß˳ï³ÝùÁ Ý»ñϳ۳óÝáõÙ ¿ í»ñç³íáñ ¹³ßï»ñÇ íñ³ ½áõÛ· µÝáõó·ñÇãáí ãµ»ñíáÕ µ³½Ù³Ý¹³ÙÝ»ñÇ ëÇÝï»½Ù³Ý ÏáÝëïñáõÏïÇí ï»ëáõÃÛ³Ý áñáß ³ñ¹ÛáõÝùÝ»ñ: Ø»Ýù ³å³óáõó»É »Ýù ûáñ»Ù, áñÁ Ù»Í ¹»ñ ¿ ˳ÕáõÙ ãµ»ñíáÕ µ³½Ù³Ý¹³ÙÝ»ñ ϳéáõó»Éáõó: ²Ûë ûáñ»ÙÇ û·ÝáõÃÛ³Ùµ ³é³ç³ñÏíáõÙ ¿ n2 k ( k = 1 ; 2 :::) ³ëïÇ׳ÝÇ ãµ»ñíáÕ µ³½Ù³Ý¹³Ù ϳéáõó»Éáõ é»Ïáõé»Ýï Ù»Ãá¹: