a(n) is the unique odd-valued residue modulo 5^n of a number m such that m^2+1 is divisible by 5^n.

A259266

a(n) is the unique odd-valued residue modulo 5^n of a number m such that m^2+1 is divisible by 5^n.

Terms

    a(0) =3a(1) =7a(2) =57a(3) =443a(4) =2057a(5) =14557a(6) =45807a(7) =110443a(8) =1672943a(9) =6139557a(10) =25670807a(11) =123327057a(12) =123327057a(13) =5006139557a(14) =19407922943a(15) =102662389557a(16) =407838170807

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