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A088935 Numbers n such that leading digits of 2^n and 5^n are equal. 1
0, 5, 15, 78, 88, 98, 108, 118, 181, 191, 201, 211, 274, 284, 294, 304, 367, 377, 387, 397, 407, 470, 480, 490, 500, 563, 573, 583, 593, 603, 666, 676, 686, 696, 759, 769, 779, 789, 852, 862, 872, 882, 892, 955, 965, 975, 985 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..47.

T. Sillke, Powers of 2 and 5 Puzzle

EXAMPLE

78 is in the sequence since 2^78 = 302231454903657293676544 and 5^78 = 3308722450212110699485634768279851414263248443603515625

98 is in the sequence since 2^98 = 316912650057057350374175801344 and 5^98 = 315544362088404722164691426113114491869282574043609201908111572265625.

MATHEMATICA

Select[ Range[ 1000 ], IntegerDigits[ 2^# ][ [ 1 ] ] == IntegerDigits[ 5^# ][ [ 1 ] ] & ]

CROSSREFS

Cf. A088995.

Sequence in context: A032122 A220818 A064678 * A183937 A030487 A165470

Adjacent sequences:  A088932 A088933 A088934 * A088936 A088937 A088938

KEYWORD

base,nonn

AUTHOR

Lekraj Beedassy, Dec 01 2003

EXTENSIONS

Edited by Robert G. Wilson v, Dec 02 2003

STATUS

approved

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Last modified October 1 23:55 EDT 2014. Contains 247527 sequences.