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
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
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