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A081990 Numbers k such that both k+1 and (product of digits of k) + 1 are squares. 3

%I

%S 3,8,24,35,168,528,624,783,1443,3843,5183,7568,8835,12543,13224,15128,

%T 17423,24335,26243,27224,41615,47523,75624,87615,92415,118335,128163,

%U 135423,172224,213443,225624,262143,265224,274575,338723,345743,374543

%N Numbers k such that both k+1 and (product of digits of k) + 1 are squares.

%e 168 belongs to this sequence as both 1*6*8 + 1 = 49 and 168 + 1 = 169 are squares.

%Y Cf. A081989.

%K base,easy,nonn

%O 1,1

%A _Amarnath Murthy_, Apr 04 2003

%E Corrected and extended by Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 06 2003

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Last modified September 23 13:34 EDT 2020. Contains 337310 sequences. (Running on oeis4.)