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%I #24 Jun 22 2018 02:48:48
%S 1,127,817,7651,13267,83167,188251,520417,751501,1332667,1689751,
%T 2519917,4691251,8331667,75015001,88015417,117206251,133326667,
%U 325510417,833316667,7500150001,9492356251,10950460417
%N Images of centered hexamorphic numbers: suppose k-th centered hexagonal number H_c(k) (A003215) ends in k; sequence gives value of H_c(k).
%C Note that all centered hexamorphic numbers end in the digits 1 and 7.
%D C. Pickover, Wonders of Numbers, Oxford University Press, NY, 2001, p. 152-155.
%H C. A. Pickover, "Wonders of Numbers, Adventures in Mathematics, Mind and Meaning," <a href="http://www.zentralblatt-math.org/zmath/en/search/?q=an:0983.00008&format=complete">Zentralblatt review</a>
%e 127 is centered hexamorphic because it is the 7th centered hexagonal number and ends in 7. 817 is the 17th centered hexagonal and ends in 17.
%o (PARI) lista(nn) = {for (n=0, nn, my(m = 3*n*(n-1)+1); if ((m - n) % 10^#Str(n) == 0, print1(m, ", ")););} \\ _Michel Marcus_, Jun 21 2018
%Y Cf. A003215.
%K base,nonn
%O 1,2
%A _Jason Earls_, Mar 18 2001