

A240924


Digital root of squares of numbers not divisible by 2, 3 or 5.


2



1, 4, 4, 7, 1, 1, 7, 4, 7, 1, 7, 4, 4, 7, 1, 7, 4, 7, 1, 1, 7, 4, 4, 1, 1, 4, 4, 7, 1, 1, 7, 4, 7, 1, 7, 4, 4, 7, 1, 7, 4, 7, 1, 1, 7, 4, 4, 1, 1, 4, 4, 7, 1, 1, 7, 4, 7, 1, 7, 4, 4, 7, 1, 7, 4, 7, 1, 1, 7, 4, 4, 1
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OFFSET

1,2


COMMENTS

This period 24 repeating sequence is palindromic.


LINKS

Table of n, a(n) for n=1..72.


EXAMPLE

The first 8 numbers not divisible by 2, 3 or 5 are 1,7,11,13,17,19,23,29; with squares 1,49,121,169,289,361,529,841 and digital root sequence of 1,4,4,7,1,1,7,4.


PROG

(Python)
A240924 = [1 + (n*n1) % 9 for n in range(1, 10**3, 2) if n % 3 and n % 5 ]
# Chai Wah Wu, Sep 03 2014


CROSSREFS

Cf. A007775, A166923.
Sequence in context: A257606 A090531 A198138 * A282468 A196463 A021695
Adjacent sequences: A240921 A240922 A240923 * A240925 A240926 A240927


KEYWORD

nonn,base,easy


AUTHOR

Gary Croft, Aug 15 2014


STATUS

approved



