|
| |
|
|
A067225
|
|
Numbers n such that n is a square and remains a square when its leading digit is increased by one.
|
|
0
| |
|
|
576, 2025, 11025, 57600, 202500, 342225, 950625, 1102500, 3515625, 5760000, 9272025, 11390625, 20250000, 34222500, 95062500, 110250000, 196700625, 351562500, 576000000, 927202500, 1139062500, 2025000000, 3422250000
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
EXAMPLE
| 576 = 24^2 and 676 = 26^2, so 576 is a term of the sequence.
|
|
|
MAPLE
| for n from 1 to 10^6 do if issqr(n^2+10^(length(n^2)-1)) then printf(`%d, `, n^2); fi:od:
|
|
|
MATHEMATICA
| f[n_] := Block[{a = IntegerDigits[n]}, a[[1]] = a[[1]] + 1; FromDigits[a]]; Select[ Range[10^5], IntegerQ[ Sqrt[ f[ #^2]]] & ]^2
|
|
|
CROSSREFS
| Sequence in context: A137484 A189990 A064254 * A036514 A188787 A168660
Adjacent sequences: A067222 A067223 A067224 * A067226 A067227 A067228
|
|
|
KEYWORD
| base,nonn
|
|
|
AUTHOR
| Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Feb 20 2002
|
|
|
EXTENSIONS
| Edited and extended by Robert G. Wilson v (rgwv(AT)rgwv.com), Feb 21 2002
|
| |
|
|