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A054215 Squares that are concatenations of two consecutive decreasing numbers. 7
8281, 82428241, 98029801, 538277538276, 998002998001, 7783702677837025, 9998000299980001, 79225472657922547264, 86432513458643251344, 92237976109223797609, 99998000029999800001, 106710893290106710893289 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..12.

FORMULA

a(n) = concatenation of A054214(n) and A054214(n)-1. - Max Alekseyev, May 14 2007

EXAMPLE

E.g. '8242' + '8242-1' gives 82428241 which is 9079^2.

CROSSREFS

Cf. A054214, A054216, A030465, A030466, A030467, A020339, A020340.

Sequence in context: A064014 A203881 A145527 * A031679 A031589 A031769

Adjacent sequences:  A054212 A054213 A054214 * A054216 A054217 A054218

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Feb 15 2000.

EXTENSIONS

More terms from Max Alekseyev, May 14 2007

82848241 corrected to 82428241 Dominick Cancilla, Jul 21 2010

STATUS

approved

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Last modified June 27 13:28 EDT 2017. Contains 288788 sequences.