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A002942 a(n) = n^2 written backwards.
(Formerly M3370 N1357)
14
1, 4, 9, 61, 52, 63, 94, 46, 18, 1, 121, 441, 961, 691, 522, 652, 982, 423, 163, 4, 144, 484, 925, 675, 526, 676, 927, 487, 148, 9, 169, 4201, 9801, 6511, 5221, 6921, 9631, 4441, 1251, 61, 1861, 4671, 9481, 6391, 5202, 6112, 9022, 4032, 1042, 52, 1062 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n) = A004086(A000290(n)). - Reinhard Zumkeller, Sep 18 2013

REFERENCES

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

Index entry for sequences related to reversing digits of squares

EXAMPLE

12*12 = 144, which written backwards is 441, so a(12) = 441.

10*10 = 100, so a(10) = 001 = 1.

MAPLE

P:=proc(i) local a, b, c, n; for n from 1 by 1 to i do a:=evalf(floor(log10(n^2)+1)); b:=n^2; c:=0; while a>0 do c:=c+(b-(trunc(b/10)*10))*10^(a-1); b:=trunc(b/10); a:=a-1; od; print(c); od; end: P(100); # Paolo P. Lava, Aug 07 2008

# second Maple program:

a:= n-> (s-> parse(cat(s[-i]$i=1..length(s))))(""||(n^2)):

seq(a(n), n=1..60); # Alois P. Heinz, May 20 2022

MATHEMATICA

Table[FromDigits[Reverse[IntegerDigits[n^2]]], {n, 1, 40}] (* Geoffrey Critzer, Dec 04 2011 *)

PROG

(Haskell)

a002942 = a004086 . a000290 -- Reinhard Zumkeller, Sep 18 2013

(Magma) [Seqint(Reverse(Intseq(n^2))): n in [1..60]]; // Vincenzo Librandi, Sep 21 2015

CROSSREFS

Cf. A000290, A004086, A080334.

Sequence in context: A309444 A198178 A013571 * A028908 A265148 A220445

Adjacent sequences: A002939 A002940 A002941 * A002943 A002944 A002945

KEYWORD

nonn,base,easy,look

AUTHOR

N. J. A. Sloane

EXTENSIONS

More terms from Jeremy Gardiner, Sep 08 2002

STATUS

approved

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Last modified February 5 03:20 EST 2023. Contains 360082 sequences. (Running on oeis4.)