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A178713 Numbers k such that the sum of the subfactorial of the decimal digits of k is a square. 0
0, 1, 2, 4, 10, 11, 12, 14, 21, 33, 41, 101, 110, 111, 112, 114, 121, 133, 141, 203, 211, 223, 230, 232, 300, 302, 313, 320, 322, 331, 411, 1003, 1011, 1023, 1030, 1032, 1101, 1110, 1111, 1112, 1114, 1121, 1133, 1141, 1203, 1211, 1223, 1230, 1232, 1300, 1302, 1313, 1320, 1322, 1331, 1411, 2000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..57.

EXAMPLE

3656 is a term because !3 + !6 + !5 + !6 = 2 + 265 + 44 + 265 = 576 = 24^2.

MAPLE

A000166s := proc(n) local dgs; dgs := convert(n, base, 10) ; add(A000166(d), d=dgs) ; end proc:

isA178713  := proc(n)issqr(A000166s(n)) ; end proc:

for n from 0 to 2000 do if isA178713(n) then printf("%d, ", n); end if; end do: # R. J. Mathar, Jan 06 2011

CROSSREFS

Cf. A000166.

Sequence in context: A186757 A184876 A243622 * A136818 A293556 A029984

Adjacent sequences:  A178710 A178711 A178712 * A178714 A178715 A178716

KEYWORD

nonn,base,less

AUTHOR

Michel Lagneau, Dec 26 2010

STATUS

approved

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Last modified September 25 09:26 EDT 2020. Contains 337335 sequences. (Running on oeis4.)