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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A371337 Numbers k>0 such that k = (sum of digits of k^2) + (product of nonzero digits of k^2).

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%I A371337 #13 Apr 20 2024 16:18:55
%S A371337 127,1467,3052,5860,653230,3483702,43352128,783820873,8092385362,
%T A371337 622196951140,1061882796441600145,178949702436677222562
%N A371337 Numbers k>0 such that k = (sum of digits of k^2) + (product of nonzero digits of k^2).
%H A371337 René-Louis Clerc, <a href="https://hal.science/hal-04507547">Nombres S+P, maxSP, minSP et |P-S|</a>, pp. 1-15, 2024.
%e A371337 1467^2 = 2152089, (2+1+5+2+8+9) + (2*1*5*2*8*9) = 27 + 1440 = 1467.
%o A371337 (PARI)  SplusP(k,r) = my(d=select(x->(x>0),digits(k^r))); vecsum(d) + vecprod(d) == k;
%o A371337         resuSplusP(p,r)=for(k=1,10^p,if(SplusP(k,r) ==1,print1(k,",")))
%Y A371337 Cf. A038364, A061763.
%K A371337 nonn,base,more
%O A371337 1,1
%A A371337 _René-Louis Clerc_, Mar 19 2024
%E A371337 a(9)-a(12) from _Chai Wah Wu_, Apr 20 2024