The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A089698 Largest n-digit number k such that k+1 as well as 1 + the product of digits of k are squares greater than 1. 1
 8, 35, 783, 8835, 92415, 956483, 9634815, 95413823, 941385123, 9857511224, 99575589135, 993574355523, 9553625719235, 99581119573155, 992553557213123, 9535746315113315, 96113351543713155, 993511252251119715, 9611213651115713535, 93112315591271511615, 963115211115325173135, 9621111711335151513615, 91735112131113523151523 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Table of n, a(n) for n=1..23. MAPLE readlib(issqr): Digits:=100: for d from 1 to 15 do for n from floor(sqrt(10^d)) by -1 to ceil(sqrt(10^(d-1)+1)) do m:=mul(j, j=convert(n^2-1, base, 10)): if m<>0 and issqr(m+1) then printf("%d, ", n^2-1): break fi od od: # C. Ronaldo CROSSREFS Cf. A081990, A089697. Sequence in context: A250889 A200312 A339325 * A133887 A200713 A184294 Adjacent sequences: A089695 A089696 A089697 * A089699 A089700 A089701 KEYWORD base,nonn AUTHOR Amarnath Murthy, Nov 10 2003 EXTENSIONS More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Dec 25 2004 Definition clarified by Chai Wah Wu, Aug 14 2017 a(17) from Chai Wah Wu, Aug 16 2017 a(18)-a(23) from Chai Wah Wu, Aug 19 2017 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified July 20 20:50 EDT 2024. Contains 374459 sequences. (Running on oeis4.)