A060201 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).

1, 127, 817, 7651, 13267, 83167, 188251, 520417, 751501, 1332667, 1689751, 2519917, 4691251, 8331667, 75015001, 88015417, 117206251, 133326667, 325510417, 833316667, 7500150001, 9492356251, 10950460417

Offset: 1

Author

Jason Earls, Mar 18 2001

Keywords

• base
• nonn

Comments

Note that all centered hexamorphic numbers end in the digits 1 and 7.

Examples

			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.
		

References

• C. Pickover, Wonders of Numbers, Oxford University Press, NY, 2001, p. 152-155.

Links

• C. A. Pickover, "Wonders of Numbers, Adventures in Mathematics, Mind and Meaning," Zentralblatt review

Crossrefs

Cf. A003215.

Programs

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