login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A188499 Intersection of A089633 and A188341. 6
1, 2, 5, 7, 23, 239 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Binomial coefficient predictors in both bases 2 and 3 (for definition, see paper in link).

Next term is > 5*10^300, if it exists.

LINKS

Table of n, a(n) for n=0..5.

V. Shevelev, Binomial Coefficient Predictors, Journal of Integer Sequences, Vol. 14 (2011), Article 11.2.8.

MATHEMATICA

aQ[n_]:= DigitCount[n, 2, 0] < 2 && DigitCount[n, 3, 0] == 0 && DigitCount[n, 3, 1] < 2; Select[Range[1000], aQ] (* Amiram Eldar, Dec 10 2018 *)

PROG

(PARI) isok2(n) = my(b=binary(n)); #select(x->(x==0), b) <= 1; \\ A089633

isok3(n) = my(d=digits(n, 3)); (#select(x->(x==0), d) == 0) && (#select(x->(x==1), d) <= 1); \\ A188341

isok(n) = isok2(n) && isok3(n); \\ Michel Marcus, Dec 10 2018

CROSSREFS

Cf. A089633, A188341.

Sequence in context: A099228 A182474 A106018 * A215535 A056921 A041245

Adjacent sequences:  A188496 A188497 A188498 * A188500 A188501 A188502

KEYWORD

nonn,base,more

AUTHOR

Vladimir Shevelev, Apr 02 2011

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 14 20:11 EST 2019. Contains 329129 sequences. (Running on oeis4.)