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A284065
Numbers whose smallest decimal digit is 4.
7
4, 44, 45, 46, 47, 48, 49, 54, 64, 74, 84, 94, 444, 445, 446, 447, 448, 449, 454, 455, 456, 457, 458, 459, 464, 465, 466, 467, 468, 469, 474, 475, 476, 477, 478, 479, 484, 485, 486, 487, 488, 489, 494, 495, 496, 497, 498, 499, 544, 545, 546, 547, 548, 549, 554
OFFSET
1,1
COMMENTS
Numbers n such that A054054(n) = 4.
Prime terms are in A106104.
MATHEMATICA
With[{k = 4}, Select[Range@ 554, And[Total@ Take[#, k] == 0, #[[k + 1]] > 0] &@ RotateRight@ DigitCount@ # &]] (* Michael De Vlieger, Mar 20 2017 *)
(* or *)
Select[Range[1000], Min[IntegerDigits[#]] == 4 &] (* Giovanni Resta, Mar 22 2017 *)
PROG
(Magma) [n: n in [1..100000] | Minimum(Setseq(Set(Sort(&cat[Intseq(n)])))) eq 4]
(PARI) isok(n) = vecmin(digits(n)) == 4; \\ Michel Marcus, Mar 25 2017
CROSSREFS
Cf. Sequences of numbers whose smallest decimal digit is k (for k = 0..9): A011540 (k = 0), A284062 (k = 1), A284063 (k = 2), A284064 (k = 3), this sequence (k = 4), A284066 (k = 5), A284067 (k = 6), A284068 (k = 7), A284069 (k = 8), A002283 (k = 9).
Sequence in context: A278798 A102388 A364680 * A063837 A344871 A071125
KEYWORD
nonn,base
AUTHOR
Jaroslav Krizek, Mar 19 2017
STATUS
approved