login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Please make a donation to keep the OEIS running. We are now in our 56th year. In the past year we added 10000 new sequences and reached almost 9000 citations (which often say "discovered thanks to the OEIS").
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A249897 a(n+1) is next smallest square not divisible by 10 beginning with a(n), initial term is 7. 5
7, 729, 729316, 7293164743396, 72931647433968832639882896, 72931647433968832639882896319584064899663299793041401 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Hiroaki Yamanouchi, Table of n, a(n) for n = 1..10

PROG

(PARI) a(n)=k=n; s=1; while(s<5*10^7, if(s%10, if(s^2\(10^(#Str(s^2)-#Str(k)))==k, print1(s^2, ", "); k=s^2)); s++)

a(7)

(Python)

def f(x):

..print(x, end=', ')

..n = x

..s = 1

..while s < 10**7:

....if s % 10:

......S = str(s**2)

......if S.startswith(str(n)):

........print(s**2, end=', ')

........n = s**2

....s += 1

f(7)

CROSSREFS

Cf. A048559, A048561.

Sequence in context: A083978 A162138 A067448 * A249834 A064571 A111476

Adjacent sequences:  A249894 A249895 A249896 * A249898 A249899 A249900

KEYWORD

nonn,base

AUTHOR

Derek Orr, Nov 08 2014

EXTENSIONS

a(5)-a(6) corrected by Hiroaki Yamanouchi, Nov 17 2014

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 December 2 10:39 EST 2020. Contains 338876 sequences. (Running on oeis4.)