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%I #14 Aug 11 2024 14:41:29
%S 0,1,17,31,177,274,280,301,313,1777,2764,3001,27259,30001,177237,
%T 300001,312208,1762122,3000001,27515125,30000001,30122098,300000001,
%U 303758458,2673533185,2817818390,3000000001,3121001208,26928832879,28255878334,30000000001
%N Numbers k such that k^2+k+7 is a palindrome.
%H Giovanni Resta, <a href="/A027722/b027722.txt">Table of n, a(n) for n = 1..45</a>
%H P. De Geest, <a href="https://www.worldofnumbers.com/quasimor.htm">Palindromic Quasi_Over_Squares of the form n^2+(n+X)</a>
%t palQ[n_] := Block[{d = IntegerDigits[n]}, d == Reverse[d]]; f[n_] := n^2 + n + 7; Select[Range[0, 10^5], palQ@ f@ # &] (* _Giovanni Resta_, Aug 29 2018 *)
%Y Cf. A027723, A027692, A027756, A005471, A027729, A027724.
%K nonn,base
%O 1,3
%A _Patrick De Geest_
%E More terms from _Giovanni Resta_, Aug 28 2018