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A109880 Numbers n such that n and its digit reversal both are difference of successive cubes. 1
1, 7, 19, 91, 127, 721, 919, 14491, 19441, 113491, 177877, 194311, 778771, 1081801, 1188811, 1767169, 1927207, 1946491, 7027291, 9617671, 16056847, 74775169, 74865061, 96157747, 129869461, 164968921, 167828761, 180676081, 189202267, 757333297, 762202981, 792333757, 1917766117, 7116677191 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A subsequence of A109879.

LINKS

Table of n, a(n) for n=1..34.

EXAMPLE

19 = 3^3-2^3 and 91 = 6^3-5^3.

MATHEMATICA

okQ[x_]:=Module[{revx=FromDigits[Reverse[IntegerDigits[x]]]}, And@@(And@@IntegerQ/@(n/.Solve[1+3n+3n^2==x, n])&&And@@IntegerQ/@(n/.Solve[1+3n+3n^2==revx, n]))] Select[Range[90000], okQ] - Harvey P. Dale, Aug 06 2007

CROSSREFS

Cf. A109879.

Sequence in context: A267378 A088988 A109879 * A245489 A084603 A088883

Adjacent sequences:  A109877 A109878 A109879 * A109881 A109882 A109883

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Jul 10 2005

EXTENSIONS

More terms from Harvey P. Dale, Aug 06 2007

23 more terms from Donovan Johnson, Feb 21 2008

STATUS

approved

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Last modified December 4 22:42 EST 2021. Contains 349526 sequences. (Running on oeis4.)