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A002942
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a(n) = n^2 written backwards.
(Formerly M3370 N1357)
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14
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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
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OFFSET
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1,2
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COMMENTS
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a(n) = A004086(A000290(n)). - Reinhard Zumkeller, Sep 18 2013
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REFERENCES
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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).
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LINKS
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T. D. Noe, Table of n, a(n) for n = 1..1000
Index entry for sequences related to reversing digits of squares
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EXAMPLE
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12*12 = 144, which written backwards is 441, so a(12) = 441.
10*10 = 100, so a(10) = 001 = 1.
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MAPLE
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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
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MATHEMATICA
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Table[FromDigits[Reverse[IntegerDigits[n^2]]], {n, 1, 40}] (* Geoffrey Critzer, Dec 04 2011 *)
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PROG
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(Haskell)
a002942 = a004086 . a000290 -- Reinhard Zumkeller, Sep 18 2013
(Magma) [Seqint(Reverse(Intseq(n^2))): n in [1..60]]; // Vincenzo Librandi, Sep 21 2015
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CROSSREFS
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Cf. A000290, A004086, A080334.
Sequence in context: A309444 A198178 A013571 * A028908 A265148 A220445
Adjacent sequences: A002939 A002940 A002941 * A002943 A002944 A002945
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KEYWORD
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nonn,base,easy,look
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AUTHOR
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N. J. A. Sloane
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EXTENSIONS
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More terms from Jeremy Gardiner, Sep 08 2002
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STATUS
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approved
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