A032750 Palindromic Super-2 Numbers.

131, 181, 333, 454, 919, 969, 1331, 1881, 3333, 6556, 9119, 9669, 10301, 10501, 10601, 10701, 13031, 13131, 13231, 13331, 13431, 13531, 13631, 13731, 13831, 13931, 14541, 16161, 16761, 18081, 18181, 18281, 18381, 18481, 18581, 18681

Offset: 1

Author

Patrick De Geest, May 15 1998

Keywords

• nonn
• base

References

• C. A. Pickover, "Keys to Infinity", New York: Wiley, p. 7, 1995.

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000
• Eric Weisstein's World of Mathematics, Super-d Number.

Crossrefs

Cf. A014569, A032743.

Programs

Mathematica

stpQ[n_]:=Module[{idn=IntegerDigits[n],id2=IntegerDigits[2n^2]}, MemberQ[ Partition[id2,2,1],{2,2}]&&idn==Reverse[idn]]; Select[Range[20000],stpQ] (* Harvey P. Dale, Jan 16 2013 *)