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Pentagonal numbers (A000326) whose digit reversal is a powerful(1) number (A001694).
1

%I #5 Mar 30 2012 17:40:35

%S 1,925,1426,6112,9801,140301,251945,578151,2112860,78883630,466005001,

%T 52244922262,394240923000,527042773467,706743866647,797657661680,

%U 869119510700,1445531162626,3905876132501,5205252778462,63253297234426,135399021815552

%N Pentagonal numbers (A000326) whose digit reversal is a powerful(1) number (A001694).

%e 925 is the 25th pentagonal number and 529=23^2 is powerful.

%Y Cf. A000326, A001694, A115695.

%K nonn,base

%O 1,2

%A _Giovanni Resta_, Jan 31 2006

%E a(19)-a(22) from _Donovan Johnson_, Jun 29 2011