

A008460


Take sum of squares of digits of previous term; start with 6.


14



6, 36, 45, 41, 17, 50, 25, 29, 85, 89, 145, 42, 20, 4, 16, 37, 58, 89, 145, 42, 20, 4, 16, 37, 58, 89, 145, 42, 20, 4, 16, 37, 58, 89, 145, 42, 20, 4, 16, 37, 58, 89, 145, 42, 20, 4, 16, 37, 58, 89, 145, 42, 20, 4, 16, 37, 58, 89, 145, 42, 20, 4, 16, 37, 58, 89, 145, 42, 20, 4
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OFFSET

1,1


REFERENCES

R. Honsberger, Ingenuity in Mathematics, Random House, 1970, p. 83.


LINKS



FORMULA

Periodic with period 8.


MATHEMATICA



PROG

(PARI) A008460(n)=[6, 36, 45, 41, 17, 50, 25, 29, 85, 89, 145, 42, 20, 4, 16, 37, 58][if(n<18, n, (n10)%8+10)] \\ M. F. Hasler, May 24 2009
(Magma) [6, 36, 45, 41, 17, 50, 25, 29, 85] cat &cat[[89, 145, 42, 20, 4, 16, 37, 58]: n in [0..17]]; // Vincenzo Librandi, Jan 29 2013


CROSSREFS

Cf. A003132 (the iterated map), A003621, A039943, A099645, A031176, A007770, A000216 (starting with 2), A000218 (starting with 3), A080709 (starting with 4), A000221 (starting with 5), A008462 (starting with 8), A008463 (starting with 9), A139566 (starting with 15), A122065 (starting with 74169).  M. F. Hasler, May 24 2009


KEYWORD

nonn,base,easy


AUTHOR



EXTENSIONS

An erroneous (duplicate) term deleted by M. F. Hasler, May 24 2009


STATUS

approved



