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A257692 Numbers such that the smallest nonzero digit present (A257679) in their factorial base representation is 2. 5
4, 12, 16, 22, 48, 52, 60, 64, 66, 70, 76, 84, 88, 94, 100, 108, 112, 118, 240, 244, 252, 256, 258, 262, 288, 292, 300, 304, 306, 310, 312, 316, 324, 328, 330, 334, 336, 340, 348, 352, 354, 358, 364, 372, 376, 382, 408, 412, 420, 424, 426, 430, 436, 444, 448, 454, 460, 468, 472, 478, 484, 492, 496, 502 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers n for which A257679(n) = 2.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

EXAMPLE

Factorial base representation (A007623) of 22 is "320" as 22 = 3*3! + 2*2! + 0*1!, thus a(22) = 2.

PROG

(Scheme, with Antti Karttunen's IntSeq-library)

(define A257692 (MATCHING-POS 1 1 (lambda (n) (= 2 (A257679 n)))))

(Python)

def A(n, p=2): return n if n<p else A(n//p, p+1)*10 + n%p

def a(n): return 0 if n==0 else min([int(i) for i in str(A(n)) if i !='0'])

print([n for n in range(1, 503) if a(n)==2]) # Indranil Ghosh, Jun 19 2017

CROSSREFS

Row 2 of A257503.

Cf. A257679, A257693.

Cf. also A257262.

Sequence in context: A081523 A310567 A310568 * A053006 A328849 A261958

Adjacent sequences:  A257689 A257690 A257691 * A257693 A257694 A257695

KEYWORD

nonn

AUTHOR

Antti Karttunen, May 04 2015

STATUS

approved

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Last modified September 18 13:54 EDT 2021. Contains 347527 sequences. (Running on oeis4.)