A061085 - OEIS

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A061085

a(n) = A019550(n) / 3.

2

4, 8, 12, 16, 170, 204, 238, 272, 306, 340, 374, 408, 442, 476, 510, 544, 578, 612, 646, 680, 714, 748, 782, 816, 850, 884, 918, 952, 986, 1020, 1054, 1088, 1122, 1156, 1190, 1224, 1258, 1292, 1326, 1360, 1394, 1428, 1462, 1496, 1530, 1564, 1598, 1632, 1666

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Table of n, a(n) for n=1..49.

Amarnath Murthy, Some propositions on Smarandache n2n sequence, Smarandache Notions Journal, Digital Library of Science, p 126

Felice Russo, A set of new Smarandache Functions, Sequences and conjectures in number theory, Smarandache Notions Journal, Digital Library of Science, (2000)

FORMULA

a(n) = one-third of the number obtained by concatenating n with 2n.

EXAMPLE

a(8) = 272 = 816/3, where 816 is 8 concatenated with 16.

MAPLE

cat2 := proc(a, b) dgsb := max(1, ilog10(b)+1) ; a*10^dgsb+b ; end proc:

A019550 := proc(n) cat2(n, 2*n) ; end proc:

A061085 := proc(n) A019550(n)/3 ; end proc: seq(A061085(n), n=1..80) ; # R. J. Mathar, Oct 10 2010

MATHEMATICA

Table[FromDigits[Join[IntegerDigits[n], IntegerDigits[2n]]]/3, {n, 50}] (* Harvey P. Dale, Aug 18 2012 *)

CROSSREFS

Sequence in context: A175670 A355031 A194374 * A007883 A023706 A043333

Adjacent sequences: A061082 A061083 A061084 * A061086 A061087 A061088

KEYWORD

nonn,base

AUTHOR

Amarnath Murthy, Apr 19 2001

EXTENSIONS

Offset corrected and sequence extended by R. J. Mathar, Oct 10 2010

STATUS

approved