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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A036435 Digits are nonzero squares. 1
1, 4, 9, 11, 14, 19, 41, 44, 49, 91, 94, 99, 111, 114, 119, 141, 144, 149, 191, 194, 199, 411, 414, 419, 441, 444, 449, 491, 494, 499, 911, 914, 919, 941, 944, 949, 991, 994, 999, 1111, 1114, 1119, 1141, 1144, 1149, 1191, 1194, 1199, 1411, 1414, 1419, 1441 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Invented by the HR concept formation program.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

S. Colton, Refactorable Numbers - A Machine Invention, J. Integer Sequences, Vol. 2, 1999, #2.

S. Colton, HR - Automatic Theory Formation in Pure Mathematics

MATHEMATICA

Flatten[Table[FromDigits/@Tuples[{1, 4, 9}, n], {n, 4}]] (* Harvey P. Dale, May 18 2015 *)

PROG

(PARI) isok(n) = {digs = digits(n); for (i=1, #digs, if (! digs[i] || ! issquare(digs[i]), return (0)); ); return (1); } \\ Michel Marcus, Aug 31 2013

CROSSREFS

Cf. A046030.

Sequence in context: A028845 A050626 A050627 * A162188 A243178 A312834

Adjacent sequences:  A036432 A036433 A036434 * A036436 A036437 A036438

KEYWORD

easy,nonn,base

AUTHOR

Simon Colton (simonco(AT)cs.york.ac.uk)

EXTENSIONS

More terms from Sam Alexander (pink2001x(AT)hotmail.com).

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 May 27 07:44 EDT 2019. Contains 323599 sequences. (Running on oeis4.)