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A082794
Smallest multiple of n beginning with 4.
8
4, 4, 42, 4, 40, 42, 42, 40, 45, 40, 44, 48, 403, 42, 45, 48, 408, 414, 418, 40, 42, 44, 46, 48, 400, 416, 405, 420, 406, 420, 403, 416, 429, 408, 420, 432, 407, 418, 429, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 400, 408, 416, 424, 432, 440, 448, 456, 406, 413
OFFSET
1,1
COMMENTS
a(n) is in {n, 2n, 3n, 4n, 5n, 6n, 7n, 8n, 11n, 12n, 13n, 14n, 15n, 16n, 21n, 22n, 23n, 24n, 31n, 32n}. - Charles R Greathouse IV, Mar 06 2011
LINKS
MAPLE
a:= proc(n) option remember; local m; m:= 0;
do m:=m+n; if (""||m)[1]="4" then break fi od; m
end:
seq(a(n), n=1..60); # Alois P. Heinz, Apr 04 2021
MATHEMATICA
f[n_] := Block[{m = n}, While[ First@ IntegerDigits@ m != 4, m += n]; m]; Array[f, 56] (* Robert G. Wilson v *)
PROG
(PARI) a(n)=forstep(k=n, 32*n, n, if(Vec(Str(k))[1]=="4", return(k))) \\ Charles R Greathouse IV, Mar 06 2011
(Haskell)
a082794 n = until ((== 4) . a000030) (+ n) n
-- Reinhard Zumkeller, Mar 27 2012
(Python)
def a(n):
kn = n
while str(kn)[0] != '4': kn += n
return kn
print([a(n) for n in range(1, 57)]) # Michael S. Branicky, Apr 04 2021
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Amarnath Murthy, Apr 20 2003
EXTENSIONS
More terms from Sean A. Irvine, Mar 06 2011
STATUS
approved