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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

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Last modified January 25 19:09 EST 2020. Contains 331249 sequences. (Running on oeis4.)