cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A226092 Fourth powers that become prime when their most significant (leftmost) decimal digit is removed.

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%I A226092 #16 May 10 2014 09:51:34
%S A226092 2401,279841,15752961,20151121,35153041,43046721,62742241,68574961,
%T A226092 88529281,200533921,260144641,547981281,671898241,2385443281,
%U A226092 2655237841,2750058481,2847396321,3262808641,3722098081,4640470641,5887339441,6414247921,8428892481,8882874001
%N A226092 Fourth powers that become prime when their most significant (leftmost) decimal digit is removed.
%C A226092 This is to fourth powers A000583 as A226090 is to as cubes A000578, and as A225873 is to squares A000290.
%e A226092 a(1) = 7^4 = 2401, because removing the leftmost digit (4) leaves 401, which is prime.
%e A226092 a(2) = 23^4 = 279841, because removing the leftmost digit (2) leaves 79841, which is prime.
%e A226092 a(3) = 63^4 = 15752961, because removing the leftmost digit (1) leaves 5752961, which is prime.
%e A226092 a(10) = 119^4 = 200533921, because removing the leftmost digit (2) leaves 00533921 = 533921, which is prime.
%t A226092 Select[Range[307]^4, PrimeQ@Mod[#, 10^IntegerLength@#/10] &] (* _Giovanni Resta_, May 26 2013 *)
%Y A226092 Cf. A000583, A225873, A226090.
%K A226092 nonn,base,easy
%O A226092 1,1
%A A226092 _Jonathan Vos Post_, May 26 2013
%E A226092 a(13)-a(24) from _Giovanni Resta_, May 26 2013