A381837 k/16 is in this list if A053737(k) < A235127(k), i.e. if digitsum(k, 4) < valuation(k, 4).

1, 4, 8, 16, 20, 32, 48, 64, 68, 80, 96, 128, 144, 192, 256, 260, 272, 288, 320, 336, 384, 448, 512, 528, 576, 640, 768, 832, 1024, 1028, 1040, 1056, 1088, 1104, 1152, 1216, 1280, 1296, 1344, 1408, 1536, 1600, 1792, 2048, 2064, 2112, 2176, 2304, 2368, 2560, 2816

Offset

1,2

Links

Table of n, a(n) for n=1..51.

Maple

aList := upto -> local k; [seq(k/16, k in select(n -> add(convert(n, base, 4)) < padic[ordp](n, 4), [seq(16..upto, 16)]))]: aList(46000);

Mathematica

Select[Range[46000], DigitSum[#, 4]<IntegerExponent[#, 4] &]/16 (* Stefano Spezia, Mar 08 2025 *)

Prog

(SageMath)
def aList(upto, b): return [n/b^2 for n in srange(b^2, upto, b^2) if sum(n.digits(b)) < valuation(n, b)]
print(aList(46000, 4))

Crossrefs

Cf. A053737, A235127.

Cf. A371176 (base 2), A381838 (base 3), A381836 (base 5).

Sequence in context: A312805 A312806 A036693 * A181471 A272753 A272804

Adjacent sequences: A381834 A381835 A381836 * A381838 A381839 A381840

Keyword

nonn,base,new

Author

Peter Luschny, Mar 08 2025

Status

approved