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A067869
Numbers n such that n and 2^n end with the same 5 digits.
1
48736, 148736, 248736, 348736, 448736, 548736, 648736, 748736, 848736, 948736, 1048736, 1148736, 1248736, 1348736, 1448736, 1548736, 1648736, 1748736, 1848736, 1948736, 2048736, 2148736, 2248736, 2348736, 2448736, 2548736
OFFSET
1,1
FORMULA
a(n) = 48736+10^5(n-1).
a(n) = 2*a(n-1)-a(n-2). G.f.: x*(48736+51264*x)/(1-x)^2. - Colin Barker, Jun 05 2012
PROG
(PARI) isok(n) = (2^n - n) % 100000 == 0; \\ Michel Marcus, Nov 23 2013
CROSSREFS
Cf. A064541.
Subsequence of A067844, A067845, A067846, and A067847.
Sequence in context: A252444 A237146 A210401 * A175278 A336189 A157667
KEYWORD
nonn,base,easy
AUTHOR
Benoit Cloitre, Mar 07 2002
STATUS
approved