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September 3, 1998
Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C. 25049-1004
Attention: Filing Desk
Mail Stop 1-4
1933 Act File No. 333-61999
1940 Act File No. 811-08103
Re: Nuveen Unit Trusts, Series 20 (the "Trust")
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Ladies/Gentlemen:
On behalf of John Nuveen & Company Inc. and in accordance with the provisions of
Rule 497(j) of Regulation C under the Securities Act of 1933 (the "Securities
Act"), this letter serves to certify that the most recent amendment to the
Registration Statement on Form S-6 (the "Registration Statement") of the above
referenced Series does not differ from that which would have been filed pursuant
to Rule 487(b) of the Securities Act. Amendment No. 1, which was the most
recent amendment to the Registration Statement, was filed electronically with
the Commission on September 1, 1998.
Very truly yours,
CHAPMAN AND CUTLER
By /s/ MORRISON C. WARREN
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Morrison C. Warren
Enclosure
cc: Alan G. Berkshire
