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 A246508 Digital root of numbers congruent to {1,7,11,13,17,19,23,29} modulo 30. 0
 1, 7, 2, 4, 8, 1, 5, 2, 4, 1, 5, 7, 2, 4, 8, 5, 7, 4, 8, 1, 5, 7, 2, 8, 1, 7, 2, 4, 8, 1, 5, 2, 4, 1, 5, 7, 2, 4, 8, 5, 7, 4, 8, 1, 5, 7, 2, 8, 1, 7, 2, 4, 8, 1, 5, 2, 4, 1, 5, 7, 2, 4, 8, 5, 7, 4, 8, 1, 5, 7, 2, 8, 1, 7, 2, 4, 8, 1, 5, 2, 4, 1, 5, 7, 2, 4, 8, 5, 7, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Period 24 repeating sequence, the digital root squares of which produce period 24 palindromic sequence A240924. LINKS Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1). FORMULA a(n) = A010888(A007775(n)). - Michel Marcus, Nov 25 2014 G.f.: ( -x*(1 +7*x +2*x^2 +4*x^3 +8*x^4 +x^5 +5*x^6 +2*x^7 +4*x^8 +x^9 +5*x^10 +7*x^11 +2*x^12 +4*x^13 +8*x^14 +5*x^15 +7*x^16 +4*x^17 +8*x^18 +x^19 +5*x^20 +7*x^21 +2*x^22 +8*x^23) ) / ( (x-1) *(1+x+x^2) *(1+x) *(1-x+x^2) *(1+x^2) *(x^4-x^2+1) *(1+x^4) *(x^8-x^4+1) ). - R. J. Mathar, Sep 22 2016 CROSSREFS Cf. A007775 (numbers not divisible by 2, 3 or 5), A240924 (digital root of this sequence squared). Sequence in context: A257452 A021142 A126561 * A144875 A248286 A049477 Adjacent sequences:  A246505 A246506 A246507 * A246509 A246510 A246511 KEYWORD nonn,base,easy AUTHOR Gary Croft, Nov 14 2014 STATUS approved

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