

A226092


Fourth powers that become prime when their most significant (leftmost) decimal digit is removed.


2



2401, 279841, 15752961, 20151121, 35153041, 43046721, 62742241, 68574961, 88529281, 200533921, 260144641, 547981281, 671898241, 2385443281, 2655237841, 2750058481, 2847396321, 3262808641, 3722098081, 4640470641, 5887339441, 6414247921, 8428892481, 8882874001
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OFFSET

1,1


COMMENTS

This is to fourth powers A000583 as A226090 is to as cubes A000578, and as A225873 is to squares A000290.


LINKS

Table of n, a(n) for n=1..24.


EXAMPLE

a(1) = 7^4 = 2401, because removing the leftmost digit (4) leaves 401, which is prime.
a(2) = 23^4 = 279841, because removing the leftmost digit (2) leaves 79841, which is prime.
a(3) = 63^4 = 15752961, because removing the leftmost digit (1) leaves 5752961, which is prime.
a(10) = 119^4 = 200533921, because removing the leftmost digit (2) leaves 00533921 = 533921, which is prime.


MATHEMATICA

Select[Range[307]^4, PrimeQ@Mod[#, 10^IntegerLength@#/10] &] (* Giovanni Resta, May 26 2013 *)


CROSSREFS

Cf. A000583, A225873, A226090.
Sequence in context: A017476 A017608 A061210 * A097015 A222461 A013845
Adjacent sequences: A226089 A226090 A226091 * A226093 A226094 A226095


KEYWORD

nonn,base,easy


AUTHOR

Jonathan Vos Post, May 26 2013


EXTENSIONS

a(13)a(24) from Giovanni Resta, May 26 2013


STATUS

approved



