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A066597 Primes which can be expressed as concatenation of powers of 6 and 0's. 1
11, 61, 101, 601, 661, 1061, 1361, 1601, 2161, 6011, 6101, 6361, 6661, 10061, 10111, 10601, 11161, 12161, 16001, 16061, 16111, 16361, 16661, 21601, 21611, 21661, 36011, 36061, 36161, 60101, 60161, 60601, 60611, 60661, 61001 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

1361 is a term as it is a concatenation of 1, 36 and 1 which are powers of 6.

MAPLE

P[1]:= {1}: R:= NULL:

for d from 2 to 6 do

P[d]:= P[d-1]:

for i from 0 do

q:= 6^i; dq:= ilog10(q)+1;

if dq >= d then break fi;

qq:= 10^(d-dq)*q;

C:= map(t -> t + qq, P[d-dq]);

R:= R, op(select(isprime, C));

P[d]:= P[d] union C;

od

od:

A:= sort([R]); # Robert Israel, Jul 31 2020

CROSSREFS

Sequence in context: A073625 A307628 A106993 * A199326 A078554 A189227

Adjacent sequences: A066594 A066595 A066596 * A066598 A066599 A066600

KEYWORD

base,easy,nonn,look

AUTHOR

Amarnath Murthy, Dec 21 2001

EXTENSIONS

Corrected and extended by Christopher Lund (clund(AT)san.rr.com), Apr 14 2002

STATUS

approved

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Last modified February 5 20:57 EST 2023. Contains 360087 sequences. (Running on oeis4.)