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A078220
Smallest k such that floor(k*Pi) begins with n (Pi=3.14159...).
2
4, 7, 1, 13, 16, 2, 23, 26, 3, 32, 36, 4, 42, 45, 5, 51, 55, 6, 61, 64, 7, 71, 74, 77, 8, 83, 86, 9, 93, 96, 10, 102, 106, 11, 112, 115, 12, 121, 125, 13, 131, 134, 14, 141, 144, 147, 15, 153, 156, 16, 163, 166, 17, 172, 176, 18, 182, 185, 19, 191, 195, 20, 201, 204, 21, 211
OFFSET
1,1
EXAMPLE
a(4) = 13 as floor(13*Pi) = 40 while floor(12*Pi) = 37.
MAPLE
C := Pi; a := proc(M0, M, C) local i, d, f, g, k; description "returns the sequence 'a(n)' between 'M0' and 'M' where 'a(n)=min{k | floor(C*k) begins with n}."; d := N->`if`(N=0, [0], ListTools[Reverse](convert(N, base, 10))); f := (K, N)->`if`(d(floor(K*C))[1..min(nops(d(floor(K*C))), nops(d(N)))]=d(N), K, 0); for i from M0 to M do k := 0; while f(k, i)=0 do k := k+1; od; g(i) := f(k, i) od; return seq(g(j), j=M0..M); end proc;
CROSSREFS
Sequence in context: A209634 A340584 A289523 * A256040 A363746 A257817
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Nov 22 2002
EXTENSIONS
More terms from Francois Jooste (pin(AT)myway.com), Mar 10 2003
STATUS
approved