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A303787 a(n) = Sum_{i=0..m} d(i)*4^i, where Sum_{i=0..m} d(i)*5^i is the base-5 representation of n. 3
0, 1, 2, 3, 4, 4, 5, 6, 7, 8, 8, 9, 10, 11, 12, 12, 13, 14, 15, 16, 16, 17, 18, 19, 20, 16, 17, 18, 19, 20, 20, 21, 22, 23, 24, 24, 25, 26, 27, 28, 28, 29, 30, 31, 32, 32, 33, 34, 35, 36, 32, 33, 34, 35, 36, 36, 37, 38, 39, 40, 40, 41, 42, 43, 44, 44, 45, 46, 47, 48, 48, 49, 50, 51 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Seiichi Manyama, Table of n, a(n) for n = 0..10000

EXAMPLE

13 = 23_5, so a(13) = 2*4 + 3 = 11.

14 = 24_5, so a(14) = 2*4 + 4 = 12.

15 = 30_5, so a(15) = 3*4 + 0 = 12.

16 = 31_5, so a(16) = 3*4 + 1 = 13.

PROG

(Ruby)

def f(k, ary)

  (0..ary.size - 1).inject(0){|s, i| s + ary[i] * k ** i}

end

def A(k, n)

  (0..n).map{|i| f(k, i.to_s(k + 1).split('').map(&:to_i).reverse)}

end

p A(4, 100)

(PARI) a(n) = fromdigits(digits(n, 5), 4); \\ Michel Marcus, May 02 2018

CROSSREFS

Sum_{i=0..m} d(i)*b^i, where Sum_{i=0..m} d(i)*(b+1)^i is the base (b+1) representation of n: A065361 (b=2), A215090 (b=3), this sequence (b=4), A303788 (b=5), A303789 (b=6).

Cf. A020654, A037459.

Sequence in context: A210436 A003004 A120507 * A090223 A171974 A232748

Adjacent sequences:  A303784 A303785 A303786 * A303788 A303789 A303790

KEYWORD

nonn,base

AUTHOR

Seiichi Manyama, Apr 30 2018

STATUS

approved

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Last modified February 18 04:48 EST 2020. Contains 332011 sequences. (Running on oeis4.)